May be the same aspect from other side..
A long during and very intensive discussion which began long before the October Revolution in Marxist crises was about how to achieve from a semi industrialized society to socialist or communist society. It was not a limited topic and with the time is opened to every direction, so in some cases lost its own frames and even targets. An interesting example was the Lenin's very harsh request to Clara Zetkin, that German socialists should postpone or better stop their passionate discussion about " liberation of woman/gender or sexual freedom issue" and but help with all their powers to young revolutions operative problems and mobilize their basis to build a large front against the growing Fascism at 1920.
Why was important at that point to think about "future" societies? OK, dreaming about coming wonderful days is always motivating but, main reason was, they knew without carrying widely basis community their construct over them has no chance to survive.
The reason that attempts to institute Marxism have invariably degenerated into dictatorships is because Marxism, much like libertarianism, is based on the naive assumption that individual humans are perfectible and that no checks on power are needed except individual responsibility.
No, Marxists from the first hour were not naive, they experienced in their own lives that theory and practice are two different things. These Avant-garde lived mostly under very extremely conditions like arrest, torture, exile, poverty, losing their comrades, not to forget most of them came from privileged upper or middle class who were not very familiar such states. Many of them broke under those conditions or changed their sides. Survivors have to think about it and they decided, they are products of their own society with its moralities and values who are not very altruistic. So, they need another kind of human being, to fight and establish the socialist society, but sprout already at capitalist society. So called "new human" so to say.
Besides the discussion about socialism, assuming the human nature never changes and stay always selfish is not logical. Approaching it to understand, may be ancient Roman society would be interesting to consider closely. Upper class was highly educated, very interested in arts and philosophy, convinced republicans and slavers! It was totally ok and having slaves was standard, they weren't seen as human, but some kind of objects as for us the our vacuum cleaner, not more. How did the humanity change this attitude? (unfortunately, still not everywhere, everyone)
Economic system is changed and time, too much time..Marxists haven't time to wait and socialist states was besieged from enemies, did not even have a little chance to wait some generations, so they tried to quicken it, just like Mao's Culture Revolution, not wait its own dynamics and they made so brutally mistakes. Nevertheless, it doesn't mean we should forget about socialist ideas.
Now, if we come back to Federation, with soo many cultures and life forms, how can you build a stabilized society form? How can you ensure your Charter will be accepted, respected or literally lived? It is a very long and painful process to build up the "Federation individual" analog to new human.
As we see, Federation is not always successful in this manner:
I think how they handle with Maquis is creepy.
We have very idealized, sophisticated Picards, but also Rambo like Siskos.
Female figures at TNG and DS9 are sometimes more archaic than 90's as the shows aired.
and so on..