I think it’s our survival instinct to hoard. I don’t think we’ve evolved to live in such a massive civilization. We weren’t meant to live this way.
I do think this level of equality would exist in older times if they knew they could get away with it.
However the scale at which we live (the global economy) is so much larger that it’s easier for them to extract and hoard wealth. In older times our communities were much smaller. The consequences for fucking around were a lot higher because it was easier for the poors to hold them accountable.