Too bad that (at least on Android an app that needs to use Bluetooth also needs GPS permission. So there's still will be a concern about privacy. I don't understand why these two permissions needs to be together.
If you don't trust the app to not localize/track you, you also don't want to give it BT permissions. BT on its own is enough to localize/track you pretty well in cities, which was one of the reasons people didn't like the idea of a centralized database of BT contacts ...
Probably because bluetooth alone could give away your location with beacons.
Could you not have a separate permission based on bluetooth profile? Not all bluetooth devices are location privacy threats to the same degree.