tax rates of the top 1% (which starts at ~$500K)

$500K-$1M....29.3%
$1M-$1.5M.....31.6%
$1.5M-$2.0M..32.3%
$2.0M-$5.0M..32.9%
$5.0M-$10M...32.4%
$10M+............30.0%

The top investment tax rate is 20% (plus 3.8% ACA surtax... not sure if that's included in the IRS stats) and the top earned income tax rate is 39.6% (+1.45% medicare + 0.9% ACA surtax). If the majority of income was coming from investment sources, you'd see those average effective rates closer to 20 or 23.8%. So a fair amount of very high earners income is being taxed at ordinary income rates.

If you look at the source of income from the IRS for the top 1%, 45% comes from wages, taxable interest and ordinary dividends, all which would be subject to ordinary income tax rates. When you add in rental/royalty income, business and partnership income, you get another ~30% which is also mostly taxed at ordinary income rates I believe.