Identity politics is quite regressive. I left that out but it's another example of 70s-liberalism and as such has become a part of the great synthesis.

I'm not sure I buy the latter part. The still-innovative cities and regions of the USA tend to be more on the socially liberal side of the divide, and if you look into the people who were responsible for all that basic invention in the past you'll find quite a mixed bag of social viewpoints from Marxism to early-SJW-ism to Naziism and eugenics to everything else you can think of.

At best I think there is little correlation between proximate political views and capacity for invention. But on a deeper level I think all of these people had a basic futuristic orientation to their thinking.

Edit: think of it this way:

Marxists, 60s "Leary era" hippies, post-WWII era American progressives, Eisenhower conservatives, and eugenicists and Nazis all believed that they were working to create a new and better world that was qualitatively superior to the existing world or to worlds of the past. They just disagreed about how and about what that new world would look like.

All the post-70s liberal and conservative regressive movements I discussed all agree that a new world is futile or foolish and that we should go back to something. They just disagree about why innovation is futile and what we should go back to.

The alt-right as the ultimate synthesis posits that we should go back to nature and the Bible and the pre-enlightenment social order. It's a totalistic anti-progressive movement.