I honestly think this is more of a reaction to Macs having had a perfectly good POSIX environment for ages, resulting in the Apple ecosystem grabbing a lot of d

I honestly think this is more of a reaction to Macs having had a perfectly good POSIX environment for ages, resulting in the Apple ecosystem grabbing a lot of developer mindshare (or at the very least developer dollars). I don't think it's at all surprising that you can't create Windows apps that run within WSL, because I don't think Microsoft see this as Windows as a desktop interface to Linux. I think they just see it as a way to get reliable installs of Postgres, Ruby, Python, whatever else, from a really good package ecosystem, in a Unixy environment that you know will work (including being able to build from source), and expose those to the Windows developer. For my part, if I'm booted into Windows I only really need enough GNU stuff to keep the Windows build of Emacs happy, and I find Cygwin makes that very easy. It's currently not seamless to try and do this with WSL, and I'd rather just dual boot if I want anything more heavyweight.