I think the Volumio is a very powerful and compelling product with a distinctive UI way above the standard of the other embedded UIs we can find in Hifi streamers.
Currently, there is a huge market opportunity: there is no decent and user-friendly Upnp control point for Android and iOS/macOS.
People like me, who has a streamer with an unusable UI, need to leverage BubbleUpnp or HifiCast for streaming music, applications that have an average UI compared to Volumio.
Or, of course, pay an enormous monthly fee for Roon.
Using Volumio as a UPNP control point, installed on a low-price Raspberry (as an alternative to a Roon Nucleus), solving the UPNP server complexities would be a perfect dream.