You are basically saying that you, from the outside, have solved the problem perfectly and the whole team of engineers at GitHub just don't know about this one simple solution you are proposing.
Have you considered that you don't have the full context of the problem and it's not "just" a few small tweaks?
My guess is that the problem is internal politics and incentives. Yes I think it is a fully solved problem for a company worth trillions to have an infinitely scalable "pull requests" page.
For example, Microsoft is known to pay significantly less than their competitors. I am guessing they just don't have the systems internally to say "This problem is worth literally billions to us in revenue per year, so we will pay millions to IC's to get it fixed and clear internal roadblocks".
It's not "just" small tweaks it is likely that people who are entrenched need to be moved and they need people with the right incentives in place to get it done.
I think we just fundamentally disagree here. I'm sure they know the current state and that it doesn't work. I think it's likely that they need entirely different people knowing about these problems and working on them in a totally different reporting structure to get the job done. It's a hard job and they're not up for the task.
I think the reason they can't make that change is that Microsoft is a slow moving rigid culture and doesn't have the kind of org that can adapt to a 10x or 100x increase in usage compared to companies like Google or the AI Labs that handled much more difficult scaling problems.
> Their c-levels wrote blog posts about the current state and why it happens, pretty sure they know what's going on.
Having read many of the formal statements from the C*Os in the BigCos I've worked for, I can say with confidence that that is not at all a safe bet to be making.
Have you considered that you don't have the full context of the problem and it's not "just" a few small tweaks?