That works only if majority agrees that we put such system in place and enforce it globally in the world. Some could say that communism was a failed attempt for this.
Why does it have to global? Isn't that just imperialism? Why can't it be scoped to a geopolitical unit that wants it?
(I'm highly skeptical of social movements that claim to be for equality, but of course there are officials who suspiciously enjoy non-equal luxuries. Then it just looks like greedy sociopaths leveraging 'equality' PR in bad faith, as a tactic.)
There are democratic countries in Africa, for example, but people in there still seek "better life" by moving to other countries, or other countries abuse these countries, because the have the wealth do so, and on individual level, it is very hard to resist some additional comfort for life if you are below certain level. People look social media and want what others have. It is very difficult problem.
Natural resources also are not distributed equally and e.g. living longer life is a basic human need. What if some other country has the technology to save humans but they don't give it for free? Some start hoarding wealth in order to get that and it changes the political attitude in general.
