things are different now. The Left will no longer tolerate the middle. At all. In fact, the Left has gotten SO far out in Left field that they think anyone to the right of Fidel Castro is a “right-wing extremist.”
This has led to a HUGE polarization. But if you look at the data, it is the Left that has gotten severely more extreme. The Right has indeed gotten incrementally more Conservative, it’s true. But not much. In that context, the Left went hog-wild and let their inner Che Guevara freak flag fly.