There was a fake MusicBee available on the MS Store a while ago. Steven had to battle MS to get it removed. I doubt he would publish anything there.
On the contrary, all the more reason to publish it in the Windows Store as it gives Steven far more leverage to get something removed if an official MusicBee app already has a presence in the store.
Honestly it makes a lot of sense to have Music Bee in the Windows Store as it:
- Increases the discoverability of MusicBee and thus the userbase as people might want a more feature-rich alternative to Groove Music and MusicBee will shoot up to the top rankings very quickly due to MusicBee being a very good high quality
application. You can bet that some tech news sites will report this.
- MusicBee's application will be hosted on Microsoft's servers vastly reducing the need for MediaFire and will be automatically updated as new MusicBee versions are published.
- Potential for in-app purchases, other developers have implemented easy donation mechanisms in the form of IAP furthering the revenue for Steven.
- Allows you to hook into various UWP APIs (even from a desktop applications) allowing for things like Live Tiles etc.
- As mentioned above, allows installation on Windows 10 S.
Now I don't claim to intimately know how MusicBee works whether any significant code changes would be required to make it Project Centennial compliant but it seems other developers haven't had too much trouble.