Thomas Piketty wrote a few books about capital and inequality: Capital in the 21-st century, Capital and Ideology and A Brief History of Equality. Most recently he gave a lecture in 2022 about A Brief History of Equality which has also been published a few months ago and for which he has a webpage with all the figures and tables he used in the lecture.

Effectively he is advocating for a more progressive tax system (more progressive than the current income tax brackets) and for a wealth tax (which would be fairer that the current inheritance/estate tax which is slowly disappearing in the US).

To be continued...