Been using this for a while actually (before the AI hype / tool integrations)
Before I used to have ~4 clones of the main work repo and then I just found that working on different things was just annoying, cause when you run out of slots, you either clone a new one or checkout a different branch... but what if you have unpushed commits / stashes for that branch somewhere else? what if you wanna open a 5th? what if you don't want to run fetch 4 times rather just once, what if you wanna try a merge between multiple things that live in different repos, you need to coordinate pushing and pulling and then try locally
My main win for multirepo was having separate .env files, but we(claude) wrote a script that could you derive a .env from our root work repo, so when I say "make new worktree" it will make a worktree copy .env from the main one changing the db credentials to be a new DB and bootstrap everything, so now I have "however many repos I want" and cleaning them up is super easy
clone --depth 1 --local would probably be slightly slower and would also work, but wouldn't solve my issue with "branches/stashes are now isolated"