Why this is not important at all:
1) Most of those people will never see combat, the military's tooth to tail ratio is like 1:3 or worse.
2) Anyone who does join a combat unit will get extended training.
3) Anyone doing the real fighting these days--aka special operations forces, get all the training they could ever want and more. Wars are not being fought by large armies in set piece battles anymore, they're being fought by "special" forces. The rest of those idiots go on to desk jobs, reserves, or "peace keeping" in countries where even the soldiers don't carry live ammunition). Most of them will end up in bars lying about how dangerous a killer they military made them.
4) This is an excellent example of the fact that the US military is far too large and could be reduced in size. Most of these recruits are unneeded. If they were needed, the tempo of the training regime would be greatly increased.
5) Hackworth, for whatever else he is, is a sellout--Fox News and the others call him up and put him on the air and probably pay him for the appearances where he blathers on and on about this or that nonsense or helps spread official government propaganda and lies while pretending to be a no-bullshit, pull-no-punches stand up guy. He probably wrote this piece to argue for more money for the DoD, as if they don't absorb enough of America's GDP as it is.
6) I'm glad to see America's youth doing more brainwork on the matter of soldiering and militarism--it's better for America that people would want to be in McDonald's managerial trainging that going out and being the cannon fodder for a bunch of politicians who don't give a damn about anyone but themselves.