I always thought that communism has been proven not to work multiple times throughout history.

The more accurate lesson would be that communist nations have been defeated by capitalist hegemony multiple times throughout history, mainly during the Cold War; the countries didn't just implode of their own accord. Now, it's fair to criticize them for this, if you have an ideology all about material conditions and then you aren't able to survive those conditions, you probably messed up, but I think that's a very different assertion from "communism doesn't work".