When taxes were higher in the 50's and 60's, we built the interstate highway system, invented the internet, sent rockets into orbit and a man to the moon, built schools that were the envy of the world, and so much more. As a country we chose to invest in these things, and it made people wealthy. Those wealthy people understood that is was through our investment that they were able to reach great heights, and were more than happy to pay their fair share.
Then we got this idea of trickle down economics which has become an utter failure. The cuts did provide short term stimulus, but as investment in research and development declined, deficits increased and people got rich from cronyism rather than innovation.
That is why countries like China are quickly catching up to us. They invested BILLIONS in solar and totally beat us out, while we invested MILLIONS in solar. It really is not wonder why we are losing there and this is just an example of the greater problem.
When someone makes millions or billions in the USA they did it on the shoulders every American who invested in them, and made it possible for them to thrive and it is only natural for them to pay it forward so that others can invent, innovate and achieve; making life better for everyone.
All these cries of "socialism" are meaningless if they just reinforce the idea that we shouldn't invest in ourselves so that innovators and achievers can do their magic. It is just plain fact that the investments we made in the 50s and 60s ALLOWED us to be the world leader in a VERY capitalist way.