> I get that WSL is revolutionary for Windows users

It is... I'm working these days on bringing a legacy windows only application to the 21st century.

We are throwing a WSL container behind it and relying on the huge ecosystem of server software available for Linux to add functionality.

Yes that stuff could run directly on windows, but you'd be a lot more limited in what's supported. Even for some restricted values of supported. And you'd have to reinvent the wheel for a few parts.