What I want at this point is a classic.github.com which uses the old UI from 2013. That was perfect and fast.

The bigger point is not about "a better UI", it's about having control over plain text. My issue with things like Jira/GitHub/Slack is not that they don't provide nice UI/UX but that they do that each on their own terms - I can't easily edit a Jira comment without having to deal with their shittiest wysiwyg bullcrap; I can't quickly and easily extract a code snippet from a Slack message without wanting to smash my keyboard in anger. If I can see that crap on my screen and can read it, why the heck they make it so vexatiously difficult to extract it and deal with it in something else? Why do I have to go through enormous hoops, every fucking time?

Using Emacs liberated me from wasting my energy for crap like that. Why would I ever complain about GitHub changing/not having/breaking their UI, if I just want to browse files and the well-trodden path for doing just that has existed in my tool belt for years, why wouldn't I just use that?

But github now handles so much more traffic, without a doubt. I'm not so sure their infrastructure is keeping up, but if it is, the current sluggishness may just be its speed under any load.

If you want to see what it should be, check any forgejo/codeberg repo.