Eliminating the favorable taxation of capital income compared to labor (and most other) income is eliminating a feature of the status quo tax system, which amounts to major capitalists seizing wealth from everybody else.
^This. It's easy to see this when you look at the numbers that show productivity rising while lower income wages stagnate. Higher income earnings have gone up an extreme amount. We've built a society where gains in productivity are not shared and that's not an accident.