I said in my comment that return on capital should be taxed the same as labor income.
> That's exactly what Piketty has shown to be false. If you look at stuff like endowments and sovereign funds you'll see gains that are nowhere near what's possible even for funds that have $100M in capital.
Do they really outperform a basic index fund strategy? Any data on this?
There isn't a market that offers better risk adjusted returns than than what is available with affordable index funds.
The only exception are probably the index funds of Dimensional Fund Advisors. They are only available to investors that have an approved financial advisor.