While Bluetooth Mesh is a thing, I'm kind of thinking that it might be time to rethink the usefulness of Bluetooth as a WAN for the sake of mesh networking in general.
Essentially, why is this on by default and next to impossible to turn off? We've tested this at an outdoor furry convention on a very limited basis to test the possibilities, and one problem that was immediately apparent is the inability (or at least extreme difficulty) in using devices like headphones or headsets, or peer to peer file transfers, over Bluetooth with Serval running.
Really seems like Bluetooth should be an opt-in mode, particularly for promiscious meshing, rather than an always-on feature, particularly now that we're on the "wifi AP" model for wifi compatibility, de-emphasizing the mesh aspect on the client side. As well as that even casual users now use bluetooth Airpods by default with their device for normal conversation.
At this point the way Bluetooth is handled as an always-on service when Bluetooth is enabled is at best really, really cumbersome for those intimately familiar with their hardware and how Serval works, tending towards a legitimate showstopper for casual users.