My theory is that the major parties are currently going through another swap of ideals, so the free-speech absolutists don't have a home.

The regions that give the strongest support to the Democrats, like Marin County in California, don't want anything built, are actively kicking out ranchers that have lived there for generations, are adamantly against anyone calling anyone else something offensive, and are in general against what was classically liberal.

Meanwhile, rural Texas counties that give the strongest support to the Republicans are for worker protections, generally against government-prohibitions on insulting someone, are increasing in their support for populism, and so on.

The Democrats used to support free-speech absolutists, who are no longer welcome there, but the Republicans are just opening up to the ideal, and don't fully support it yet.

I am not even sure it’s a swap. I see a lot of RW sentiment lately that libertarian principles are self-defeating, and the only thing that matters is Straussian friend-enemy distinction.

Basically, the extreme wings of both parties are seizing power and preparing for battle, while the moderate wings are tuning out. (Or to put it another way, more of the center is becoming politically independent.)

Traditional ideological lines break down under these conditions, because the important thing is damaging your enemies, not maintaining ideological consistency.