You're not seeing the big picture. If Windows can do Windows apps and also 90% of what Linux developers use Linux for, what need is there ever for Linux on the desktop? MS marketing may be trumpeting their love for open source but WSL2 is a actually a brilliant bit of jujutsu[0] on Microsoft's part.
[0] I use this word specifically because it's a martial art about using an opponent's strength against themselves. MS's use of Chrome as the basis for their new browser is another example of this.
Microsoft saw developers flock to Mac OS/X where they had a true terminal and could also run line of business apps like Office. I was at several Microsoft developer conferences where 90% of the machines were MacBook Pros and I know that didn't make Microsoft leadership happy. I believe the Surface line was a direct response to that along with WSL. Someone in Redmond realized they couldn't beat Linux so now comes the embrace.
> This means that code written for this will NOT function on desktop Linux.
Like CUDA, I assume that most applications would not be coded to this API directly. Microsoft already mentioned OpenCL and OpenGL.
This is to hardware accelerate Linux applications and not to create WSL-specific Linux apps. I can't imagine there's a big market for Linux GUI apps that would only run on Windows.
Someone please correct me if I'm wrong but I interpret this as being only a bridge to DirectX from the Linux kernel. Not a DX implementation on Linux.
You won't be able to take this dxgkrnl driver and load it into a Linux workstation and get DirectX.
And also, someone else responded to you what's the point of running Linux if Windows can do everything Linux can.
I would assume that most full time Linux users are using it out of at least a tiny bit of ideological motivation. And if not ideological then habitual, having had the power and granular transparency of Linux for so many years that Windows would never be an alternative.
[0] I use this word specifically because it's a martial art about using an opponent's strength against themselves. MS's use of Chrome as the basis for their new browser is another example of this.