Rojava is a decentralized capitalist region

And the USSR was a centralised state capitalist system. China has even left the "state" part behind and is nowhere nearer abolishing class than it was at the start of the revolution. It actually regressed in that regard.

But, fine, call Rojava that if you will. Just shows how you can't see any possible roads to communism that don't involve the failed experiment that is state capitalism.

though it was managed centrally by the EZLN

The EZLN does not manage centrally. The EZLN is not even a governing body. It's a decentralised milita that councils tasked with matters of military security. It is those councils which are the governing body, not the EZLN. Rojava operates alongside the same lines, though details differ because cultural, material, and other differences.

I know it might be incomprehensible to you: A literal army, with all the capability it could wish for to order the local population around, sat down with the local population and told them about their ideas. The population then told them about theirs. They discussed, mutually refined their ideas until there was a consensus on how to move ahead, leading to what you see now. No shot was fired, noone was sent to gulag. They've also been capable of large organisational reforms, deliberated to consensus, implementation happened just a couple of months ago.

Maybe you should set aside some time and actually study those regions, not just read tankie cliff notes about how they supposedly work, or don't, or are secretly authoritarian, or whatever.

The Bolsheviks who established the USSR were also “social democrats”

The Bolsheviks were never democrats and the French social democrats still call themselves communists. But that's rather besides the point: The Cuban revolution was in the late 50, by then the split between SocDems and communists (both liberal and authoritarian) was not just done it had hardened. Heck the revolution ended in 59, after the word tankie had been established, which was 56, in direct reaction to the Soviet invasion of Hungary.

The point I'm making here is that Fidel & Co came to the US, said "We're eyeing doing something like your European allies are doing and want to be friends, you know, unions, welfare, worker's rights", the US said "nope, can't have you not be slaves to Bacardi and United Fruit you're our colony after all", Cuba said "never mind then we thought we could be friends then we'll go with our second choice, the USSR". The USSR, then, demanded from their allies a heavily authoritarian slant, so Cuba adopted it, in the interest of national survival not out of preference. Which is also why they are by far the furthest along among the surviving ML states when it comes to democratisation. Vietnam is second, with quite some distance, China makes no moves in that regard and North Korea, well, North Korea is only ever getting worse, not better. Oh, Eritrea. Same.