I find it almost amusing that every time MS does something related to Open Source, you get comments from people who feel MS hasn't moved past the "embrace, extend, extinguish" years. They seem to prefer to ignore the fact that MS has drivers to support various Linux flavors on Hyper-V and Azure, that you can spin up a pre-built Linux VM in Azure (using big-name Linux flavors such as Red Hat I believe.)
Corporations, like MS, are in the game to make money. There's money to be made in Open Source and MS is now realizing that fact.
So, do I think the doomsayers who feel MS is going to make GitHub worse, perhaps by moving functionality behind a paywall, are right? No, not in the main. I think what will happen is MS *will* have some functionality added that will require a subscription to access, but the current state of GitHub will remain unchanged (except for branding.)