You nailed it. There is no "normal" with Dems except what they decide for us.
There is no slippery slope. That's just stupid. But, they will "evolve" themselves (total misuse of the word, of course) when they feel the need to create a new form of bigotry for political gain, and then they let us know periodically how far the bar has moved.
Evil preaches tolerance until it is dominant, then it tries to silence good.