humans in power will always want more

That’s the kind of bullshit “human nature” argument that liberals use to justify bourgeois “democracy.” No, not every person who has power develops some inevitable insatiable thirst for more. Power structures will always exist, certainly within socialist movements but even within anarchist movements. Just because we live within a capitalist structure that rewards greed and sociopathy while punishing empathy doesn’t mean we can’t build power structures that truly benefit the whole of society.