>>15134297china's super capitalist tbf, and has been since deng. a lot of the tiananmen square protesters were socialist students angry at the communist party's increasing economic liberalisation
but i'd say the reason communism has failed so often is because it's either done with nationalism in mind (cambodia), because it's sanctioned to hell and back (cuba, which while successful compared to its peers is still in a sticky situation), because the cia coups or kills their leader, even if democratically (chile, attempted in venezuela) or because there was so much domestic or international turmoil that the state had to centralise its power, thus making it harder to let go of that power after the crisis had passed, like lenin in the russian civil war; much of the anti-democratic measures were implemented as temporary measures until the war was over, and he had only started relinquishing that control when he died. stalin wasnt exactly known for his egalitarianism so he decided to bring things back to civil war levels of authoritarianism even in peace time, and unfortunately set the tone for 20th century socialism.
but if you look at places like rojava or the EZLN, or even anarchist catalonia before the tankies/stalin sold them out, they seem (or seemed, in the case of catalonia) like they're actually making meaningful progress in moving on from capitalism to a more socialist, egalitarian, decentralised economic and political structure. which is pretty cool