Azure is a cash cow. Windows brings in money but is increasingly difficult to monetize _and_ its increasingly difficult to keep bringing legacy app support forward and stay competitive.
PowerShell, .NET Core, and MS SQL are all happily running on Linux.
By all accounts WSL entered the market with little drama is pretty great to use (IMHO).
The idea of doing a native SSH from WSL into a Linux container on Azure running a bootstraped 'MS' version of *nix with official support for a discounted price compared to a Windows VM is certainly appealing.
I would run MS Linux as a dev environment in a heart beat. MS would do well to _not_ to brand a desktop and just run a very clean gnome or plasma default.
Then a dedicated app store can really push PWAs like Teams,Skype and fully manage the interop layer for other apps that need a little more hand holding (wine, mono, etc).
tl;dr - I'm into this.