This is one I'm okay with. Git submodules are absolutely awful.

I recognize that some folks are stuck with it, and yeah, in your case jj probably just doesn't make sense. Stay tuned though.

It just means that you use git commands to update your submodules, jj still works for the rest of the repo just fine.

I have a repo where main has no submodules and a branch has submodules. Switching between then breaks everything...

Yeah, this is annoying right now. Someone is actively working on a patch to improve it, though.