RN isn't tied to the UWP app model nor the Store. It's built on the UI framework that was created for UWP, but (as the link for this thread mentions), that can

RN isn't tied to the UWP app model nor the Store. It's built on the UI framework that was created for UWP, but (as the link for this thread mentions), that can be used outside the UWP app model (currently via XAML islands, in future via WinUI 3) and apps in the UWP app model can be distributed outside the Store anyway. In my personal opnion, it might be a good thing that apps that can read each others' memory, etc. can exist, but they shouldn't be the default, users should have to explicitly opt in to allowing that, and not in a way that will become just another dialog box for most people to mindlessly click OK on.