The US has the most progressive taxation system among all developed nations. Nothing about that fundamental progressiveness has changed due to the tax cuts. The top 20% are paying 95% of all income taxes, that will continue.
For example, the US is radically more progressive on taxation than all of Scandinavia:
The (conservative) Tax Foundation article totally ignores that Norway also has an individual wealth tax (0.85% on assets above about USD $179,000), which is quite progressive compared to income taxes. They also have higher capital gain and dividend tax rates than the US (which the article mentions).
But the top tax rate has been steadily declining since the Eisenhower administration. This tax bill furthers that decline. Over that period we've seen an increase in inequality. Are they correlated?
I'm not sure the bit about what share of income tax is paid by the wealthy is meaningful here, outside of right wing think tank PR releases (your linked site is funded by the Koch Brothers btw. Just a heads up).
>The top 20% are paying 95% of all income taxes, that will continue.
You are comparing population with taxes, when you should be comparing wealth to taxes. Of course people in poverty with no tangible income or net worth don't pay income taxes. The wealthy in the US pay far, far less in taxes as a percentage of their wealth than any other developed nation in the world. In addition, the taxes paid by people in all civilized developed nations pay (either in part or in whole) for healthcare and education instead of bankrupting working citizens for basic needs. Working people in the United States pay far more in taxes and receive far less than any other developed nation - but at least we have our wars.
If you look at the statement "The top X% of the population hold Y% of the wealth and pay Z% of the taxes," it turns out that Z > Y for most values of X.
> The US has the most progressive taxation system among all developed nations.
That's extremely misleading; the US does functions other developed countries do via social welfare programs via the tax system (deductions and credits such as the EITC, tuition and student loan interest deductions, etc.)
Doing a like-for-like comparison—either removing the welfare system pieces out of the US tax system in the comparison or, even moreso, doing an all-in comparison of tax + transfer payments, would tell a very different story.