It's totally compatible though, and that's a big selling point. I use jj and nobody else at my work uses it and that has never been an issue.

I think the "incompatible" was more in the dvorak sense, which I believe is that whenever you are on another computer, it most likely won't have dvorak.

For jujutsu, it's fine on your own computer, but you probably have to use git in the CI or on remote servers. And you probably started with git, so moving to jujutsu was an added effort (similar to dvorak).

It doesn’t support submodules. So no, not totally compatible.