I’ll answer that... NOTHING. They are trying to steal it and claim it their own as proprietary. It has already been predicted that MS would try this if we let them try to integrate or support anything Linux period. Soon it will be “well from what I understand, you cannot use Linux unless you have windows to run it?”.
Watch, here it comes...
I doubt they'd be successful at that. Instead I see this as a desperate move to remain relevant to software development.
Microsoft is playing catch-up with the software dev and dev/ops community. Linux became the preferred dev environment many years ago, not just because it's a better environment, but also when it became clear that Linux was going to take over the internet via "cloud" services and containers (docker, Kubernetes, etc.). Which it has done, in large measure. Windows simply cannot do what Linux does, and people want what Linux does.
Add to that Microsoft's dismal and utter failure in the mobile market, where Linux rules via Android.
Thus, running a Linux (dev) environment on Windows is a desperation move by MS to avoid Windows development being shunted into the corner completely by 2025 or so.
All that said, Windows will remain the majority user platform for a long time -- it's simply too entrenched to be forced out of hundreds of millions of homes and businesses. Windows applications will continue to be the default. But modern software development abandoned Windows years ago, and MS finally realized it.
I'm glad they did. I'd like to see Windows remain relevant for more than doing Excel spreadsheets in Accounting and playing video games.