I'd argue that the dominance of Linux on cloud and Azure growing business is what's causing Microsoft to have an ongoing interest in linux support.
A factoid that's shared sometimes (no idea if true) is that Microsoft now employs more Linux kernel engineers than Windows kernel engineers due to Azure.
That came after. Linux wasn't even on 2.6 with its famous stability yet when this kicked off. What you see now is a result. They softened on open source as they realized it actually has some benefits for a company like Microsoft.
The Microsoft of the Halloween Documents[0] is a different Microsoft from the one we see today that understands open source as something good rather than as a threat, and it started with Microsoft being forced to play nice.
After having gouged Red Hat and Suse for years with their bogus Linux patent racket and bankrolling the infamous SCO Unix lawsuit. Make no mistake M$ coming over all We Love Linux was like Donald Trump turning up at the DNC.
I do remain skeptical that the node on the Microsoft org chart that usually strangles anything good the companies does is waiting to strike. It used to be Windows node, but now it seems like the ad node comes in for the kill most of the time. The company is slowly morphing into Google as Google morphs into Amazon, while Amazon is morphing into UPS.
Off-topic but to join in the general good vibes this announcement emanates: i have to say that my experience using Azure cloud has been stellar. Their co-pilot integration works well, IME. Azure shell is simple and good. Dashboard UI is always good.
Bona fides: I have used GCP for 3 years, AWS for 3 years, and Azure for ~ 1 year. As well as the more "bare-metal" types of cloud providers like Linode/Akamai, and Vultr -- all the latter of which are great for self managing your infra.
I also really find the ability to spin up Windows Server and Windows 10/11 etc super useful for builds, testing, Hyper-V.
I really like Azure for huge projects with many moving parts.
A factoid that's shared sometimes (no idea if true) is that Microsoft now employs more Linux kernel engineers than Windows kernel engineers due to Azure.