> You can UNDO. Everything. That is the major thing
Everything is what? The things git cannot undo is removing untracked files (well they're untracked) on git-clean, or files added to the index for the first time and then reset. Maybe rebase in mid-rebase is a way to lose some changes so one has re-rebase again (it's really annoying, but reflog holds all rebase changes if I recall). I can't really see what you mean.
> You can switch from one `branch` to `another` and leave things incomplete, even conflicts, that is nice.
It's nice. I use git-worktree for multiple branches I work on, so my working copies may remain dirty even in conflict stage.
> The command made sense
It's nice.
> Nobody else knows you use `jj`, so no barrier to adoption.
It's really nice, but I'm not sure whether I understand it, but does it work as a front-end tool over git/other VCS?
> Rebases are not painful anymore. Stacking prs are finally nice to author, even of NOBODY ELSE KNOW IT!
I don't get it. What does make rebase hard? It's just re-applying a bunch of patches or possibly merges on top of the new base, and it doesn't even require interactive mode. Interactive mode makes magic I'm happy with. Seriously, what's wrong with it?