It wouldn't, just don't let them get to 40pop, and even if they do, just back cap it.
that would actually be kind of cool for a game mode, if they put in the maus, have it take 35-40 pop, axis goal is to hold enough ground to bring it out, once it's out, it's pretty much an iwin button, but one player will have no other armor, and there's still the possibility of allies being able to out cap after its brought out.