It’s all about developer tie-in. It’s far too easy to move your stuff between azure and aws. Microsoft needs to create differentiation and barriers to migration and since github is heavily used by developers who use both azure and aws, it is the obvious attackpoint. “Well I use azure because the github admin interface makes it easy to deploy, you can’t do that to aws from github...” etc.
Now depending on how evil(tm) Microsoft intends to be, they will either just only focus future development on integrations towards their own stuff, or they will actively degrade github when you aren’t going Microsoft across the board.
I feel like if it is the latter, Github will quickly lose market share to non-Microsoft competitors. Developers on the whole seem to care a lot more about those kinds of tactics than computer users in general. Surely Microsoft understands this and doesn't try this kind of fuckery.
Now depending on how evil(tm) Microsoft intends to be, they will either just only focus future development on integrations towards their own stuff, or they will actively degrade github when you aren’t going Microsoft across the board.