GitHub is going to turn into the FOSS version of the MySpace wasteland. I'm sure GitLab and other alternatives are seeing a stampede of new sign-ups right now.
The question isn't really what MS will do, because - as is often the case - it won't matter.
MS bought Nokia Phone, trashed the company, flailed around dramatically for a while, and in the end nothing much changed in the phone space - except that WinPhone hung on for a year or two longer than it would have otherwise.
MS bought Skype, trashed the product, bolted it awkwardly onto Office, and in the end nothing much changed, because anyone with any sense moved to an alternative.
It's going to be the same with GitHub. There will be drama in the short term, but in the longer term MS will receive little or no benefit, except for maybe some closer integration with VS.
The money will simply be wasted.
The real winners will be the investors and owners of GH, who have walked off with a big pile of MS stock they can convert to money and use to buy nice things.
Just hope most go to a common place which appears it will be GitLab.
You know that Gitlab is also VC backed, right? They have to exit in the same way as Github did. It’s baked into their DNA. The only question now is who buys them. What will you do if that’s Oracle?
github wanted to make money from their paid services to create a profit. microsoft couldn't care less about the money paid github accounts make (as long as it's not hemorrhaging too much), it's unlikely they'll get a ROI from paid accounts in anyones lifetime.
they need github to increase their earnings elsewhere, e.g. by getting developers to develop for the microsoft store or for their cloud services. so my guess is they'll at least start advertising their tech heavily on github and add features integrating their own tech while omitting the same for rivaling corporations.
the old github didn't have an interest in limiting integration with other platform providers, as this would decrease their usefulness for potentially paying developers.