I think most just want OST to have a 50% win rate, rather than 37% (and USF/Sov having nearly 60%).
As for the rest of your comment, it's just been a slow general 'shift' towards OST being under-performing - not any specific change. I'd guess the 'shift' started just after WFA was released, since OKW was incredibly powerful back then (volk schreck blobs). Instead of fully nerfing OKW, they were only nerfed partly, and USF/Sov were buffed to meet at a mid-point. Meanwhile OST got received nothing.
Now we're in a situation where mainline infantry blobs can beat an MG42 head-on, where grens aren't dominant at max range (they trade w/ vet 3 M1919 rifles and double Bren-IS), and where the panther's high mobility doesn't compensate for its shorter range as a TD (M36 is faster with more range).
Again be happy that OH has been played this tournament, for the last one where it barely was picked(Command panther). OKW grand offensive is just too good. So only worse players choose OH in the first place resulting in lower winrate
To the rest of your post. Ostheer was barly touched in the last years and for a good reason, becouse it was and is a very good balanced faction. If anything OKW was brought in line with the other factions. But where are the significant buffs over the last lets say 2 years that broke ost? The small riflemen buff surely didnt. Cons 7 men and svt sure did. But those are getting adressed this patch.
Ostheer actally got significant buffs -100mp for t2, vet3 grens that dont get oneshotted. And ofc the bane of OH pack howi and scott got nerfed.
So again where was the patch that broke ost and started this crywave? All of the issues your presenting are old, so you wanna say OH was severly underpowered the whole time and peaple just noticed?
So to conclude, OH might actually be in a better spot than 2 years ago if one adresses the overtuned cons. (which is WOP)