Their infra is under constant DDoS + they provide a lot of free stuff for open source projects. There's also a constant churn of dependencies, patches, abandoned libraries, etc. We should give them some appreciation, dealing with this stuff is hard.
If they are genuinely compute constrained on CI they should obviously reduce the free offerings rather than take down all their paying customers constantly.
Have you considered that you don't have the full context of the problem and it's not "just" a few small tweaks?
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.
Their c-levels wrote blog posts about the current state and why it happens, pretty sure they know what's going on.
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.
Have you seen this legendary email thread from 2003 https://www.osnews.com/story/19921/full-text-an-epic-bill-ga...? This isn't a new problem at Microsoft.
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.
It is also constant outages, and then it's your job to diagnose and fix it- and the technical work of that is the easiest part.
It's broken because a team figured out a new way to abuse the company's git infra to get around some process or limitation, and now you have to argue with their manager and then their director about why their team needs to stop using your VCS as a docker registry or whatever.