The difference being that the definition of "hate speech" is a slippery slope, closely connected with the euphemism treadmill. The difference being, usually the euphemism treadmill doesn't have any legislative import...

Examples off the top of my head: the demonization of "illegal" when in reference to people who cross the border without the right to do so.

The willful conflation of "Muslim" as a race rather than a religion.

Why exactly is it a slippery slope? I admit that it can be made as such, but why must it necessarily be? A legislature or person can define hate speech in such a way that it is not a slippery slope in my opinion, and I think that's what should be done.