https://learn.microsoft.com/en-us/shows/internet-of-things-s...
I would rather say UNIX won the server room, Linux just happens to be the UNIX clone most people hack on nowadays, and can change tomorrow as companies take over and people like Linus eventually pass the torch.
You can already see that on embedded, other FOSS OSes are being adopted, without GPL licensing, like Zephyr, NutXX, FreeRTOS,...
But the fact that they’re rolling a distro tells me they’re likely also writing software for Linux. I’m sure their Azure Linux contains apps they wrote and maintain, used by the OS.
Then there’s Microsoft apps on Android, with Linux under the covers.