> While I do use old.reddit and genuinely think it's better UI-wise, in the general case users tend to be resistant to any UI change because it breaks their habits and muscle memory.

It's funny how often people say "it's just habit / muscle memory / etc." in response to these kinds of discussions, as though it were somehow a counter-argument, and not something that corroborates the argument against making sudden, drastic UI changes.

It's really weird how common it is for people to say "well, Y is only true because of X" in response to "Z doesn't work because of Y", and thinking they're somehow defeating the argument against Z. If you acknowledge that X exists and causes Y, and accept that Y isn't compatible with Z, then you are conceding that Z does not hold!