I'm not totally certain you can attribute it to this. I know there's a bunch of work going on to migrate things into Azure after the MS acquisition but it feels like more of an industry trend that we cut engineering spend at the cost (often) of lower quality output and outages like these.
GitHub laid off 10% of their staff in 2023 and like you say, won't have slowed down to account for that.
Ignoring all that though... other than Copilot, what big feature changes have you seen in GitHub? My experience of using their product has been broadly unchanged for years.