So we may not agree on which premium tanks are explicitly overpowered, but we can all agree that there are overpowered premium tanks. The leFH, E25, and Defender are all premiums that I believe are generally seen as overpowered by the community.
Wargaming keeps talking about "Balance 2.0" or whatever, but what does it really matter if they won't touch the premium tanks? What can be done to resolve the problem?
Here's what you do – WG goes ahead and balances premium tanks. Obviously tons of people will be pissed off but honestly, there is no precedent for people receiving money back because a digital item they purchased was "nerfed", and tons of other games do this. And to alleviate some of that anger, you can offer an exchange system – if you no longer want a premium tank that you purchased due to a nerf, Wargaming will have a "grace period" similar to the one issued for WoT premium where you can trade in the tank for the tank's full gold value +25%. For a limited time, all premium tanks in the game would be made available for gold. It could be a huge event as part of the planned "Balance 2.0" thing, and if Wargaming markets it in the correct way it could go off pretty well.
Besides, after the supposed huge incoming game rebalancing, some premium tanks may just no longer fit with the meta. If the game has a massive re-balancing I can't see any reason why a person wouldn't want every tank in the game to be balanced, including premium tanks.
And on another note, there are plenty of garbage premium tanks too. Why not balance those as well?