You don’t even need to tax it at 80% because if you did billionaires would move elsewhere (see…
Mark Suster
28717

I am generally sympathetic to tightening the spread between LT Cap Gains and Ordinary Income — but, let’s remember that such a change is already underway. In the last three years, the spread between Cap Gains and Ordinary Income has narrowed substantially. This has happened both as states raise taxes (since state tax has no capital gains) and as Obamacare went into effect. It also took place in 2013 when Bush-era tax cuts expired and Cap Gains were disproportionately increased. The delta is now much narrower, and my guess it that it will slowly diminish over time.

It seems that you don’t believe in any delta between Cap Gains and Ordinary Income. That is a fine opinion to have, but I think that most people do believe that a small incentive for starting companies is reasonable. The narrowing process, though, is well underway.