If you notice all infantry units are not called infantry, instead they are listed mostly by the weapon of chc and stats indicate that. For instance
Buffalo soldier
Garand
Marine
all use the m1 garand and thier attack values are the same. You’ll also notice some tanks with the same caliber gun have the same attack value also.
shermans are the same, except the the ones with special cannons.
M18GMC
M18 Helcat
M-10
all the same attack values, except for the m-10 has a slightly better long range infantry attack but I think we know why, because it had a kick butt machine gun on the back… I think it was a 50 caliber.
So the question is what gun does the tank commander use when he hops out, a hand gun? Maybe the tank’s 30mm machine gun? This is the problem. Same for a Bazooka, you’d think if there’s not more tanks to fight he’d just drop his Bazooka and pick up a rifle. Units are the units and can not change duing the game except for the resoureful hero.
Besides a tank commander would never leave a functional tank.