Communism

Workers of the world, unite!

I mean the ruling class of Russia, China, and Iran, can also be my enemy.

The ruling classes of maybe Russia and Iran can be considered "enemies" (although if you live in the west, they don't have any power and little influence over you), while the ruling class of China is neutral for westerners (and positive for the Chinese) in the most cynical reading.

Furthermore

1. Believing in the narratives of your ruling class is why you have such a negative perception of these governments in the first place. Otherwise, Russia and Iran's repressive policies are not more repressive than most countries outside the west (and let's be real, they are barely more repressive than the west)
2. These countries are playing a military role in dismantling western imperialism, and you should use this as an opportunity to weaken your ruling class, which is infinitely more bloodthirsty than Russia or Iran's ruling class, and also maintains a global system of super exploitation whose downfall is the only way forward for humanity. Unless of course, you know of anyone else who is militarily opposing the west (Yemen is the only one else).

No need to be choosy when you can instead have solidarity with the mistreated and exploited around the world :)

The exploited and mistreated of the world in general have a net positive perception of Russia, and China precisely because these countries have a continued track record of helping these countries. And this is especially true with China.

No, other capitalist powers arent, but you have more in common with a random Russian than Warren Buffet, just as they have more in common with you than Putin and his fellow billionaires.