The problem isn't capitalism, well it's not JUST capitalism. If you give any group of individuals that level of wealth control, the same pattern repeats. They can be shareholders, board directors, or commissars or general secretaries of the people's party, a prince or a duke, or the first citizen.

It doesn't matter, all you need to replicate the same problems is concentration of wealth and power and the ability to direct it.

Indeed. It's just that capitalism produces immense concentrations of wealth as a core feature of the system.