All too true...

I've been watching since Nixon, though I should admit that I didn't do politics much for a lot of that time period. So, in that respect, I guess I'm part of the problem.

Since Reagan, though, the Repubs have driven farther and farther to the right. With that, liberal Repubs (yes, there used to be some of those around) and what we would think of as 'moderates' gravitated to their only option, the Dems. Consequently, the Dems have drifted and been pulled farther and farther to the right themselves, to where a few cycles back (think Clinton's first term) they actually crossed over to being a center-right party on most issues instead of left or center-left.

To compound the problem, as Repbubs got farther to the right, they became more and more extremist, and less open to any forms of compromise. Dems have been reluctant to drop their belief in compromise. This was showcased in the Obama presidency, where the Repubs categorically avowed that their main goal was to block everything the President tried to do, which they did, including many proposals that were decidedly not progressive or liberal in their implementation, the ACA being a huge example of this. It was somehow a 'miracle' that it passed, but it was and is in essence, a RW, corporate based solution to a problem screaming for a progressive, liberal one.

We've gotten to the point where any suggestion of progressivity or liberalism triggers an automatic response of "oh we couldn't do that." There never seems to be any vigorous response of "Why not?" to that rather vacuous statement. The country does need a huge shot of progressivism and liberal action, and we can't seem to get it.

As to the thought behind the OP, IMNSHO the Right is to blame as primary instigators, but the left, such as it remains, has been complicit and enabling in the process.