Think of it like this, capitalism is the middle ground on the sliding scale between feudalism and socialism.
As the curves even out more people gain the opportunity to benefit from as of yet eradicated selfish commercial infrastructure, meaning we went from Royal Kings with swaths of countries and resources in their sole ownership, to Corporate Kings where any person who starts their own little capital exploitation racket can be the king of their own little business kingdom.
Thus as we move closer to socialism, more people will gravitate towards accessible personal benefit through selfish exploitation of remaining loopholes until parity of income is reached and selfishness no longer benefits the individual, resulting in socialist utopia.
Will the oligarchs let this happen? It certainly doesn’t look likely in my generation, especially in the US (where it looks unlikely for much much longer).
We had feudalism and it's selfish precursors ever since man started working together, let's be generous and say about the time agriculture started so approx 6000ish years ago and it took that long to get to a "halfway mark" and still only about half the planet has functioning democracy, and like any good project the last 10% takes 90% of the time, but technological advancement gave us instant global communication so social development already has the maximal social access, increasing the speed of the development of social consciousness, this will only increase as people have more free time to engage with other people instead of survival, so a conservative estimate would put social utopia somewhere around 4,000 years from now. Give or take.