My usage isn't high. I was rate limited to like 5 requests per minute. It was a repo with several small files.
And seriously if they keep this up, with limits on their web interface but leave unauthenticated cloning allowed, I'd rather clone the repo than log in.
GitHub code browsing went south since microsoft bought them anyway. Having a simple proxy that clones a repo and serves it would solve problems with rate limits and their awful UX.
Since Microsoft is struggling to make ends meet, maybe they could throw a captcha or proof of work like Anubis by xe iaso.
They already disabled code search for unauthenticated users. Its totally plausible they will disable code browsing as well.