The Marine Corps is much more of an elite, shock troop, assault force and is normally MUCH smaller than the Army. The Army can afford to have two enlisted tracks, as they have had since the War Between the States, off-and-on. I left as a Spec/6 and wasn’t great NCO material, but I wasn’t in the combat arms. Far from it.
Not to beat a dead horse, but I agree and think the Army did a great disservice to itself and to a lot of soldiers when they did away with the specialist career tracks for the reasons I mentioned previously and others...