I don’t think any nation has on average better or worse player.
This is an English speaking forum, and its not hard to see most people here play US as their main tree. And its not really something you can expect everyone to have multiple trees ground out past ww2 BRs, taken me thousands of hours just to finish Russia/German air and ground, and I’m just now finishing Russia, 2 tanks left, + spading and playing some I have unlocked. So its hard for most people to actually get multiple perspectives on trees. Actually hard is a too soft a word its pretty much impossible to expect your average player to.
The war has done nothing but pump insane amounts of anti Russian propaganda everywhere in the west, and add that on top of Americans generally being very proud and pumped up about their military and its a recipe for what these forums are, 80% US mains complaining about Russia or their own vehicles. Its rare to see Germans complaining besides what 2 threads recently about their ww2 planes being overtiered, and a single thread about leo not being able to depress behind. I don’t think I’ve seen any threads in weeks complaining about russia tanks in terms of them being underpowered etc., just having to defend them in the countless threads complaining about them or nato tanks.