Why are you comparing it with Arietes? that comparison is based on the assumption that the Russian TT player base has the same average skill level as the Italian TT players, which is quite far from the truth. You need to compensate for the player skill base difference before making that comparison. This would be hard but thanks to the copy-paste T-72A and T-72M we can do this:
RU T-72A: Win rate: 46.3% K/S: 0.96 K/D: 1.09
IT T-72M: Win rate: 49.4% K/S: 1.07 K/D: 1.25
Edit: I used the May stat in the Screenshot, the data I wrote was the overall stat. Still, the May stat proves my point even more.
The reason I choose these two is that they are the only completely copy-paste MBTs of the closest BR to 11.7. If we use this to normalize the Arietes stat with this difference, we get:
Ariete PSO (Normalized): Win rate: 47.1% K/S: 0.94 K/D: 1.08
Ariete (Normalized): Win rate: 47.5% K/S: 0.98 K/D: 1.13
And my god these stats look way worse now, in fact far worse than the TT BMPT.
As for the M1A1 situation, yes they are pretty good, in fact they are not THAT different from the 12.7 variants. But still, RU still has a overall higher winrate for 11.7 and 12.0 BR than US. Comparing May 2026 stat on statshark, we get:

So, um, we do see the problem here don’t we…
Or if you are gonna argue that the high winrate was not with the BMPT still being OP:
Well they kind of still are: They are the most popular spawn, they are played by majority of the RU players, they therefore get the overall weakest player base. But they still get the highest K/D of all the 11.7 RU tanks. They ARE the backbone of that all green winrate, and therefore they ARE OP.
Edit2: Ignore the T-80UM2, that thing is a event tank, people owning it has overall better skill than the general data set.