Looking at 2007 was a peak in both income earned and taxes paid. Comparing it to today, income earned (as a %) decreased, yet taxes paid (as a % of total) is about the same.
So we can at least say from 2007 to now, tax burden increased.
The tax burden for the top 1% _income_ earners can totally increase while the tax burden for the top 1% wealthy decreases (they earn from dividends, not work)
So we can at least say from 2007 to now, tax burden increased.