Also: I always hear Marxists refer to “socialist states” as if non of them ever reached statelessness. I wonder why.

It's good to be curious! Marxism posits that classlessness and (therefore) statlessness can only be reached once all is Socialist.

And trying to make a stateless country while half the world is capitalist and you are under constant threat of invasion and CIA sabotage, while the (former) capitalists are working to reintroduce capitalism, is at best foolish, and at worst sabotage, betrayal of the people.