And why weapons with such weapon profiles shouldn't be in game?
"Because I think so" is not a valid answer.
Ignoring multiple weapons because they do not support your point is also not valid move.
Don't cling zealously to balance decisions that are no longer present in coh2 for more then 4 years now.
Timing and cost also play a factor.
Relative positioning is a good design idea that was thrown away the same time most good design ideas were--when WFA was released.
However I see little fault in limited doctrinal options being better than the non limited non doc ones. For example say the m1919 and BAR were swapped. You pay 70mu for a 1 at a time weapon that changes rifles from aggressor to defender, the BAR being doctrinal but unchanged remains attractive in that it can be double armed (or mixed and matched) as well as enforcing their mobility. Similarly the mp40 vs stg for volks. Ooooo smoke and a small rec acc buff in exchange for long range firepower AND have to give up the lava nade? It's like having the DSHK doctrinal and a call in Maxim..the Axis examples you gave have their own drawbacks- spec ops is a doctrine with only 4 slots, falls is a tough one to master the balance of MP and muni strain the OKW doesn't usually have to deal with. Fussies is boring to play (OK not the best argument but it's got its own problems).
G43s offer a role change on squishy infantry. Stgs/BARs raise the threshold without changing anything else.
Penals transition form beating the shit out of anything they look at to slapping away light armour/nuking slowed armour. No Brainer transitions are bad design. Give us some dynamics some PROPER choice