Why does bluetooth (still) only support pairing two devices?
Bluetooth 5 allows up to 8 connections at a time.
Android P allowed up to 5 audio devices connected at a time (developer mode), but active streaming was still only allowed to less at a time.
The standard allows for more than what developers want to support. Google or Samsung or whomever doesn't think anyone wants or needs to stream music to 5 audio devices at a time, and the more you can stream to the more complicated the coding and debugging would get, for diminishing returns. Basic cost vs benefit analysis. Both iOS and android drop features every release because the majority of people don't really use them.