Communism is about fully collectivized economy globally

quoting wiki:

A communist society entails the absence of private property and social classes,[1] and ultimately money[6] and the state.[7][8][9]

For me the result is among others anarchism (absence of state/money). Anarchism itself is probably not communism per se, but I consider it a part of "full communism".

absolutely fits with human nature, which itself is malleable and depends on given material conditions.

I really would like that to be true, but I don't see how... As I said, we never had anything close to it, whereas we had/have something very close to pure capitalism (looking at you USA...), fairly stable (not a good thing, IMO, as we see especially currently with climate-change and growing inequality). Also for China: autocratic State-capitalism (mostly at least), probably better than whatever USA currently is, but still capitalism, and definitely not communism.

What I meant with "doesn’t fit in human nature" is basically described in https://lemmy.world/post/50376887/25196710 So yes for small-scale, very likely no at (especially) a global scale... The egoism and hunger of power of a few manipulative individuals will likely always prevent this unfortunately, also the "fear" of foreign stuff (like people/migrants), and the difference of global (natural) wealth, like fertile soil etc. I think having social contact with most people within such a society is almost a requirement (i.e. trusting individuals of the society), which is why I don't see how we can achieve something like that globally, distrust and (often irrational) fear is probably the deal-breaker per se for that.