Couple things here: Communism is Socialism, a form of it. Communism has never been “implemented” either, as it’s specifically a post-Socialist stage. The ML states you’re referring to were Socialist, and didn’t reach Communism.
Secondly, the ML states were ML states, and as such were deliberately adapting new theory proposed by Lenin and distilled by Stalin.
I’m in no way a Stalinist, or a simp for the USSR, your comment is just wrong.
By your very same logical chain, Capitalism is an ideology 400 years old that failed miserably every time, as well as Socialism. It’s meaningless word salad.