This is more or less how Phabricator (dead, but lives on as Phorge[1]) works. It uploads/downloads patches via HTTP.
IMO, using Git remotes but with a one-review-unit-per-commit approach like Gerrit has a much better UX. Shipping around diffs has all sorts of sharp edges, especially when you stack multiple changes or binary data, and you end up reinventing native Git functionality but worse.
Phabricator started out as "paste your diff here" and eventually ended up with a CLI tool that reinvented half of the Git CLI.
IMO, using Git remotes but with a one-review-unit-per-commit approach like Gerrit has a much better UX. Shipping around diffs has all sorts of sharp edges, especially when you stack multiple changes or binary data, and you end up reinventing native Git functionality but worse.
Phabricator started out as "paste your diff here" and eventually ended up with a CLI tool that reinvented half of the Git CLI.
[1]: https://we.phorge.it