By years you mean literally just the last patch. Technically Dec 2019 to Feb 2020, okay, but you're really clutching at straws when it comes to "years" here.
Dec 2019 patch get rid of the potential model bust from 16 dmg rifle of sections and heavily neft their out of cover performance. But event before that, with the rng model bust, stum still charge and beat sections in cover with 3 models. The issue happened for years, dec 2019 patch just make it worse.
Applying "the same logic" would be incredibly stupid since they're literally not the same situation. Volks vs Rifles is a mainline vs mainline situation and not a mainline vs single CQC specialist situation. Volks vs Rifles is a fair fight at long range, whereas everyone, even Combat Engineers and Rear Echelons, will dominate Sturms in a long range engagement.
There's literally nothing similar about those two situations.
Stumpio is not CQC specialist, they are "mid to close oriented unit which happen have good close dps", said by Vyper, not me. And it is just opinions problem. I bring in the comparison mostly with trolling intend, but sure, you can take it serious all you like.