I love WSL, but giving this a major upgrade label (2 to 3) seems a bit of a stretch, at least from the viewpoint of an average dev user.
Perhaps it reflects the amount of work and thought that has gone into it, but I really think the optics are better if the selling points are immediately obvious to the user.
Hopefully some light will be shed in further blogs.
Especially given 1 -> 2 was a complete rewrite that changed the entire architecture to the extent that there are still reasons to run WSL 1 in some cases. Talking of which, the one thing I'd be excited about (if I ever expected to do any dev on Windows again, which I don't) would be a way of sharing local storage between Windows and Linux processes without incurring a massive slowdown on one side, which WSL 1 achieves, but it doesn't sound like this has that. (Or does it?)