PoE doing +48v? Now that's cutting edge!
Yes it's -48v if that's what you are mentioning.
I would imagine as digital gear is comodotized several things will happen (some are happening)
1 - The A/D will continue to get closer to the sound source at both ends of the chain
2 - Generic complex instruction set CPU's will be powerful enough (if they are not already) that it is only a matter of time before a passable softmixer engine as released, maybe even open source first. BITS timing could come from a USB high stab or some such
3 - Live sound DAW surfaces will appear
4 - Inexpensive A/D's with as few as one port will exist.
Meta data could be moved with the channel data for the scribble strip snake that was mentioned.