The Democrats have screwed up by appealing to the “fringes”. That’s who they got beat by a celebrity with no political experience.
Think of the image of a yard stick.
In the old days the “center” was the center. Then the left started going further left on the stick, insisting that they were still near the middle. As they did so more and more became the right and then the extreme right ... less and less became the extreme left.
Right now the political yardstick is only the last inch of the old extremely extreme left, a couple of inches they allow as centrists, and everything they call right wing.