cliffvb: Great points. And people who have been sitting on long-term capital gains but have modest income will be taxed as though they are wealthy. For example, a retired person sells AAPL stock held for 10 years with a profit of $400K. Together with his or her other income, people like this will be in the top tax bracket, which will be AT LEAST 39 percent. Throw in the State tax, and they will lose 52 percent of their profit (California residents), 46 percent (Maryland residents), etc.
The migration to Texas, Florida, Arizona and Washington would accelerate.
AND, retirees' Medicare Part B premiums would triple two years after the sale of the stock. Ditto for Medicare Part D Premiums. The increase would be one year.
And we haven't even discussed inheritance taxes. Inherited wealth is evil to socialists. I'll leave it at that.