A super simple fix is to encourage the rich to have more children. If they have 6 children and divide their wealth 6 ways, that rebalances wealth inequality every generation.
Easy enough to do via tax policy too. Eg. 10% tax reduction per child.
This is generally the case anyway. The problem is that one lifetime is plenty of time to accumulate enormous capital and do enormous damage. In fact, I care almost exclusively about the problems that they will cause during my lifetime.
