Here are just a few issues caused by free market capitalism alone, without government intervention.
https://www.economicshelp.org/blog/77/economics/problems-of-capitalism/
The root issue is that currency is cohesive - it attracts itself. If you have a lot of wealth, it's very easy to make lots of money. If you have no wealth, it's very difficult to make any money. This effect is compounded over time and generations.