Please look up “wealth inequality over time”, or watch this video on the topic https://m.youtube.com/watch?v=EdqxBNgnmxU
Wealth directly represents control over resources and ownership of the economy. The more wealth you have, the more power you have (under capitalism) so massive disparities in wealth are also massive disparities of power
I think the critical difference is that communism has never had a chance to be tried without capitalist countries attacking them. Capitalist Nazi Germany invaded the Soviet Union and then the Capitalist USA forced the USSR into an economic cold war. Then the US bombed the shit out of socialist countries for 50 years. Communist China was threatened with a economic cold war if they didn’t join the “free market”.
But we have tried capitalism for 300 years and it produces horrible atrocities: leaded gasoline, mass starvation in 3rd world countries, child sweat shops, slavery, sex trafficking, destroying the planet for profit, billionaire oligarchs destroying democracy, etc