Those center lefts maintained a status quo that did not serve it's constituents, plain and simple. Say what you will about Trump, hate the dude and his policies, but he has a base who has some very regressive desires, and he's hitting them. Democrats have a pretty large progressive base, and they have essentially failed to meet those desires for as long as I've been alive. But maybe they needed a dog in the white house to bite them in the ass. We will see. Or we won't and the world ends, whatever!