I bet the author discovered the problem during an AI coding session. The "mathematically sound" comment sounds like the AI did some deep dive into a possible corrupted private key before checking for a missing public key. Maybe it's a claw-type system that automatically publishes a blog post when something interesting happens. Either way I flagged it.

GitHub is big. They'll be doing lots of things all at once. This is probably just a case of some normal component replacement for some maintenance reason. I'm as frustrated as anyone about the lack of stability and the hard pivot to AI, but this at least shows they're doing work on this area of the application.

For all we know this could be a knock on impact from an upgrade or component replacement for improved stability. Maybe even critical security fixes. I don't think it's fair to lambast them for doing work around the core git/ssh systems.