I'd say a lot BP can be shaved off in the example used with specializations. For instance, instead of Demolitions 2, he only needs Demolitions 1 (Plastic Explosives) (or Standard Army Explosives, if you're willing to go with custom specializations), instead of Etiquette 3 only Etiquette 1 (Military or Chosen area of interaction), etc.
Aye, good point. Assuming specializations still are +2 dice they let you shave off a LOT of points in some cases. Defaulting is also very generous in Shadowrun.
Let's look at the SR4 skills and useful specializations, since I assume they are not going to be radically changed in SR5.
Archery: Niche skill. Possibly a 'boot camp' skill for some NAN militaries to emphasize ancient traditions (as opposed to bayonet training, for example). Specialty: Bows.
Automatics: Bread and butter. Specialty: Carbines or Assault Rifles.
Blades: Niche skill. Note that bayonet training has been dropped from most modern training courses. Specialty: Knives
Clubs: More likely to be taught that Blades, honestly. Probably more a part of infantry training. Specialty: Batons.
Dodge: I'm up. He sees me! I'm down! Specialty: Ranged Combat.
Exotic Melee Weapon: Unlikely.
Exotic Ranged Weapons: Most of these are not very good anyways. ERW (Lasers) is the most likely.
Heavy Weapons: Depending on your branch of service you may never even
touch one of these. Otherwise bread and butter infantry skill. Specialty: All are useful (well, assault cannon is dubious).
Longarms: Should never have been separate from Automatics in the Shadowrun level of detail. Oh well. Specialty: Shotgun would be most popular, but Sniper Rifles for marksman and snipers.
Pistols: Not as universal or useful as you might imagine. Most officers carry the service weapon, not a pistol these days. Specialization: Semi-Automatics.
Throwing Weapons: Most will just default, but grenades are pretty crazy good in Shadowrun ... Specialization: Lobbed.
Unarmed Combat: Practically universal now, and way more useful than the old bayonet training. If nothing else you learn some weapon retention techniques and takedowns. Specialty: Subdual Combat.
Climbing: This is not "climbing a rope" and most will default. Specialty: Rappelling.
Disguise: Honestly, most will default. This is more than using camo makeup. Specialty: Camouflage.
Diving: Combat swimmers will obvious learn it. The specializations as listed are a cluster. Specialty: Military (whatever that means) or SCUBA.
Escape Artist: Maybe if you go to escape and evasion courses. And even then probably just default. Specialty: Zip Ties (these damn things are ubiquitous).
Gymnastics: Probably default. The Unarmed Combat training usually includes a lot of practice in parts of this, though. Specialty: Breakfall.
Infiltration: You would be a
fool not to have at least minimal training in this in 2074. Specialty: Thermal Imagers, Urban, or Wilderness depending on role and operational environment.
Navigation: Most default now, in 2074 it's a dump skill except in edge cases. Specialty: Depends on operational environment.
Palming: Not really a useful military skill unless you are a shifty motherfucker by nature. Specialty: Shoplifting.
Parachuting: The specializations are a cluster. Obviously a core skill for airborne units and special ops. Specialty: Low Altitude.
Perception: Usually trained up on-the-job, but ASIST training can do wonders. A
core military skill in 2074. Specialization: Visual.
Running: Most default, even the rabbits (guys who smoke the running part of fitness tests). Not really a military skill per se, honestly. Specialization: Sprinting.
Shadowing: More for special ops and military police types. Specialty: Tailing.
Survival: Most default. You have an entire organization behind you that does the work for you most of the time. Specialty: Depends on operational environment. May be learned on the job in some shithole situations.
Swimming: You'll learn to at least float and not too anything
too dumb when you default. Naval infantry and crew will learn some actual skill, but nothing amazing unless they already love to swim. Specialty: (New) Survival.
Tracking: Pretty edge case, but NAN special ops have to deal with a lot more beasties and Awakened problems so will probably emphasize this. Otherwise bring in the local guide. Specialty: By operational environment.
Con: learned on the job when you become an NCO.

Information ops personnel may get training in the scientific methods for lying by carefully not lying. Also may be useful against some types of interrogation where
misleading isn't the same as
lying. Specialty: Fast Talk.
Etiquette: The military is its own culture, with a surprisingly broad geographic range and crossover across nations. Specialty: Military.
Instruction: NCOs and officers receive actual training in this. Specialization: Varies, but most get by with just the general principles.
Intimidation: Special ops may learn it. Some NCOs and officers may pick it up on the job. (For a harshly realistic campaign this is usually a default with some situational modifiers based on rank, and not really indicative of any actual skill. A civilian probably wont give a shit what some Master Sergeant has to say but Private Shmuckatelli has other considerations). Specialty: Interrogation.
Leadership: Rarer than you might think! Actual
effective Leadership that is. Officers and NCOs are taught the skills, but most default and a surprising number are outright Incompetent at it. Shockingly, Shadowrun combines this with Strategy and Tactics! Oy. Specialty: Tactics and Strategy. A natural leader may have Morale.
Negotiation: Not really a military skill, but logistics personnel often learn it on the job. Specialization: Bargaining. (Shitbirds (lazy asses) will have an uncanny talent for Sense Motive.)
Aeronautics Mechanic: Obviously a skill for guys and gals who work the flightline. Specialty: Depends on duty assignment. Mostly Fixed Wing, Rotary Wing, or Vector Thrust.
Armorer: Unless you are an actual armorer, you're going to be defaulting. This skill goes
well beyond "you can field strip that carbine like a god made flesh." Specialty: Depends on duty assignment. Most armorers will have Firearms, Heavy Weapons or Weapon Accessories. Unit mechanics and will have Armor or Artillery. Combat engineers will ahve Explosives.
Artisan: For engineers this is a core skill (well, not Guitars and stuff). Specialty: Carpentry.
Automotive Mechanic: Mechanics obviously learn this at their school, if they didn't already have it. Specialty: Usually Tracked or Wheeled.
Chemistry: Not really a military skill. Bring in the civilian specialists to take a look. Specialty: Toxins.
Computer: Assuming this skill does anything useful for cybercombat defense, it's a no brainer to harp on during basic training and beyond. OPSEC. OPSEC. OPSEC. Specialty: Commlink.
Cybercombat: The military spider learns this. Specialty: Maybe IC. Hard to tell what is most useful.
Cybertechnology: Not really a military skill that troops will know. The rear echelon docs will know this though. Specialty: Can't go wrong with Bioware or Cyberlimbs.
Data Search: More of a general knowledge skill. Specialty: Government.
Demolitions: Combat engineers can be expected to master this. Infantry and special forces are also going to have some training. Specialty: Defusing or Plastic Explosives for most. Special ops and insurgents often learn the finer points of Improvised Explosives.
Electronic Warfare: This is a very broad skill that most military personnel will be expected to master to some degree. Specialty: Communication or Sensor Operations are the go-to specializations. Encryption and Jamming are more traditional EW tasks for signals intelligence and spiders.
First Aid: Bread and butter skill, but rear echelon folks will just default. Specialty: Combat Wounds.
Forgery: Not really a military skill. Specialty: False ID.
Hacking: Core skill for military spiders. Specialty: Varies.
Hardware: Probably largely outsourced, but there will be some people in signals and computer support who will know this. Specialty: Commlinks.
Industrial Mechanic: Core skill for most mechanics and engineers. Specialty: Electronic Power Systems and Structural are the most useful for expeditionary uses. Robotics is very important because of all the drones (again, you can outsource a lot of that maintenance).
Locksmith: Not a military skill. Specialty: Varies.
Medicine: Actual medics will have some skill in this, as will the docs behind the lines. Specialty: Trauma Surgery.
Nauticl Mechanic: Day-to-day maintenance doesn't require a huge skill investment, but you can't default to it. Some naval personnel pretty much do this and nothing else since fighting corrosion and other issues is a never ending battle. Specialization: Ship or Submarine.
Software: Spiders learn this to some level, but they also have a whole army of experts that can provide them the best ware right out of the labs.
Gunnery: Because of how the skills work, this is a core competency for infantry and even many non-grunts will know it. Specialty: Ballistic, Energy, or Guided Missile are the most common.
Pilot Aerospace: Only a few military pilots actually need this. Most that do are more in a support role, not expected to engage in hostilities. Specialty: Remote Operation and Suborbital.
Pilot Aircraft: Fighter pilots, transport bubbas, and panzer drivers need this. Specialty: Fixed-Wing, Remote Operation, Rotary Wing, or Vectored Thrust depending on what they fly.
Pilot Anthroform: Not much of a need for this for combat troops. Anthroforms are useful for logistics though. Specialty: Remote Operation.
Pilot Exotic Vehicle: Not much role for these.
Maybe PEV (Jet Packs).
Pilot Ground Craft: General skill useful everywhere. You'll probably end up learning a specialization in the military either because of your job (logistics or supply), random bullshit ("We have a slot for Combat Hovercraft training this winter, no one wants to go so Pvt. Schmuchatelli takes the hit."), or personal interest (you have your own car or bike). Specialty: All of them are useful.
Pilot Watercraft: In the Navy. Technically there are specific jobs tied to specializations in most modern navies, but in 2074 it's probably a core competency due to low manpower. Specialty: All of them are useful except Sail.
Language: You're going to learn a lingo. It's practically an in-joke that you can carry on entire conversations with someone in a different MOS and not have a
damn clue what the hell they are saying. for game purposes I would just use <Language> (Military Jargon).