This is the problem with people promoting socialism. They tend to compare idealized version of socialism with real version of capitalism. And such comparison inevitably leads to unrealistic conclusions.
The problem is that real version of socialism is what you see in China or Cuba or former USSR. The argument with “we haven’t done socialism right” is the same as “we haven’t done capitalism right”.
I have been born in socialist country and to this day I can see negative consequences of that era. And the obvious reason why ideal socialism can’t exist - people. Same reason why capitalism sucks.
Edit: To people downvoting me: Your fake internet points have no meaning, but I love the irony of it. You can’t even keep the illusion of classlessness and equality in an internet thread, yet you are somehow convinced you could run a country like that. You’d be locking people for life in your communist paradise just for having different opinion and you know it.