If you're talking about P2P over cellular, I think it's just in general a bad idea. The way cellular networks are operated, you can't do device-to-device connections - they have to go through the tower for a number of (very good) reasons. That's where the latency comes in, and the wireless transmission latency can be an order of magnitude higher than the latency on a cross-country connection. Furthermore, the resource that is constrained is the amount of available spectrum - so we need to optimize for that. Bandwidth is effectively infinite from the tower to the cloud, but bandwidth from the tower to the device is the constraint.

P2P over non-cellular (i.e. Wi-Fi or Bluetooth) where you can actually make a direct device-to-device connection seems like it may have some use cases (messaging apps, etc.) But they're edge cases and by no means a common use case because it just isn't reliable enough.