"I thought looking at the aggregates that the top 10% pay something like 1/3rd of all income/cap gain taxes."

This is because much of the income of the wealthiest families in the country never appears on their income tax returns. https://www.americanprogress.org/article/forbes-400-pay-lowe...

What matters is the top 10% generates wealth through investments/equity/asset appreciation- stuff that the tax code barely touches. The bottom 90% is locked into W-2 labor.

The tax code gives capital gains a massive, legal pass- for those that can afford to exploit it.. aka, the ultra rich are paying far less taxes then they should be.