I hope you will continue maintaining a mirror in GH. Some tools like deepwiki are excellent resources to learn about a codebase when their is not much documentation going around. But these tools only support pulling from GH.
Git pulling isn't unique to github and it works over http or ssh?
That being said, there's no reason for tools like it to have those constraints other than pushing users into an ecosystem they prefer (i.e. GitHub instead of other forges).
Demo: https://tools.simonwillison.net/cors-fetch?url=https%3A%2F%2...
https://git.dillo-browser.org/dillo/plain/src/ui.cc?id=29a46...
It's also not being served via a caching CDN, which means I don't feel comfortable running anything automated against it as that might add load to the server that they aren't ready for.