For all the hate it gets, the GPL protects from exactly that. Microsoft would need to publish all changes in the copyleft components of the shipped OS.

Which is why you add non-copyleft components and make them not really optional. Like for instance their directX-based graphics and cuda support.

Sure, the "core" stuff is protected and you could do without the optional things for now. But how about when for example your favorite machine learning software says "we support linux, but cuda is only supported under WSL", similarly for graphics, rendering etc. .

Sounds a lot what Google is doing with Android (open source) and Play Services (not). They made on purpose harder and harder the use the former without the latter.

Most of the components would be outside of kernel, so it would not be GPL.

The majority of Linux distributions including Debian and Ubuntu have a GNU userland which is GPL licensed.

The notable exceptions are Android and some distributions and toolkits that target embedded systems such as OpenWRT

Linux without GNU is very far from a desktop Linux distribution experience that most users would recognize.

I don’t think counting distributions is the best metric. The majority of hamburger makers are individuals barbecuing at home, but McDonald’s dwarfs them.

Counting users, I guess Android has over 50% of them.

Counting installations (probably one of the fairer methods), I still would think Android has over 50% of Linux installations. Google gives me numbers in the million for the number of Google and Amazon servers, not always for recent years, but I guess they won’t have a hundred million servers combined.

(And of course, there’s the philosophical discussion whether Android is a Linux distribution, or something that uses a Linux)

There's also tons of embedded Linux devices, from your TV, your car, your fridge, home networking equipment... I don't know if theres enough of them to outweigh the massive number of phones in the world, but I think it's enough that Android wouldn't cross 50%, at least in north america.

Only if they distribute it to third parties. If they make it cloud-only and sell access to it but not installs for it, they're fine.

Someone else did it first,

https://www.android.com/

https://www.chromium.org/chromium-os

That's what WSL is though. LSW is unlikely.

What do you mean with this? GP is saying they wish for something that, as far as we know, MS isn't even considering.