It’d make a lot of sense to integrate it if it’s possible, I think. The design direction of Git is somewhat subservient to the needs of Linux (i.e. Git is a thing Linus made to replicate BitKeeper, but it also was made to scratch—and continues to scratch—many of the LKML itches re: their unique patch-management workflows.)
So if Linux is having to do something re: “SCM ops” tooling, that could be better solved in Git, then why not solve it in Git?
(If anyone who was responsible for this Kernel.org Git bundle setup wants to chime in, that’d be interesting; I assume they likely considered making this a Git thing first, so there might be a good reason why it’s not.)