I use local remotes all the time for testing as a form of "local CI".
Check it out from '/tmp' and make sure it still builds.
For a single-dev or small team, it beats having to do github runner epicycles to accomplish the same basic goal. Add in Firejail if you want environment isolation.
Would git worktrees be useful in that use case? It just adds a new checkout in a different directory without duplicating the git data (blob storage).
I do the same sometimes, but a one-off clone is not quite the same as maintaining a "local remote" and pushing refs to it.