Hungary isn't trying desperately to hold onto "single most powerful country in the world" status. The US being as relevant as Hungary is one of the most extreme scenarios of "The end of Pax Americana".
Well, when it happens to the level that it has under Trump, that country is in big trouble also. But noone (and I mean noone) has damaged a democratic nation as badly as Trump. There are a lot of contenders, but they all miss the mark by quite a bit.
Russia was hardly a demoncratic nation. Thatcher is close, but she is not even close to the damage that Trump has done to America. The UK recovered, the U.S. will not.