It wouldn't, and that's why they're still there—but if the Democrats were in the middle of a "purity spiral", they'd be gone. Instead they're in the middle of

It wouldn't, and that's why they're still there—but if the Democrats were in the middle of a "purity spiral", they'd be gone. Instead they're in the middle of "we've got these people constantly blocking us but they're slightly better than the alternative spiral". In other words, spinning in circles going nowhere.