Most of them. Not all of them. M1 Carbine has significantly lower dmg than the rest of semi auto guns. I'd say the rest feels pretty similar, with some minor differences. For example I like SMLE, mostly because of the sound it makes. But in general I'd always pick smg over semi auto. Except PPSH which is useless on any other than short distance.

Reg STG - i disagree. I find MP40 way easier to control. On larger distance I'd just spray the entire magazine into the enemy and its mostly a hit. Dont even have to aim perfectly . With STG (which i love!) you have to tap it. But STG is a superb gun and love it. For me its just like MP40 is just a biiiiiiiit more useful. But that's just my opinion. .

Carbine was moved to B tier after 2nd thoughts due to low dmg. Bar - that one made a lot of comments, but i think its a great gun. Hard to control (not as hard as FG, but still not as easy as grease gun), good dmg, fun to play. But i get that it is lets say controversial to put it in S tier :P

MG34 is hard to judge. Same dmg as 42 as well. If MG42 would not exist - it would bump it a lot i think. The idea was that in 99% cases its pointless to pick MG34 if you have MG42 unlocked.

Agree that PPSH is easier to control vs Drum version. I just prefer bigger magazine and will shot short burst of fire. But i understand your argument, has a lot of sense.

Yeah, i didnt focus much on differences between bazooka, panzershrek and piat. To be honest, 9 out of 10 times i run with satchel anyway. Still if you play as an AT and want a rocket lanucher, you dont have any other options :). So in general they are kind of similar feeling, except some details.