One thing of note is that this particular acquisition is not DevDiv, it's Azure ML. But Azure ML is, in some ways, even more F/OSS friendly - at least I don't know anyone else in MS running Linux servers in production for user-facing services, and it's where a lot of ex-MSR guys (like, from those labs that were closed) ended up. It's also where all the Python stuff now is.
Then again, after Satya's takeover, there was a strong push from top down to stop treating open source in general and Linux in particular as pariah, in all divisions. In no uncertain language, like "we've been acting stupid about this for a while now and let competitors eat our lunch; time to catch up while we still can". The recent slew of announcements, from
FWIW, I didn't think I'd ever hear a Microsoft lawyer utter the words "GPL is actually kinda cool" while explaining to developers the company's new open source policy in his official capacity. Yet, here we are.
Long and hard? Yes. But this kind of thing makes it worth it (and also shows that, perhaps, it's not quite all that long if you go fast enough).