Why is there a StackExchange proposal in the works for a “Musical Practice and Performance site” when KeyMinor already exists on the SE platform?

The proposed site is “for people who play musical instruments. On-topic questions will be about technique, practice, theory, composition, and repertoire.” KeyMinor already serves this purpose, it’s just not known about.

I’d add a comment to the proposal but I see no way to; I probably don’t have sufficient reputation points.