This is funny to me because I remember going to a talk at comdex years ago and the speaker kept saying “Bluetooth is coming I’m so tired of hearing this” and then he made a sarcastic comment about how Bluetooth would connect his belt and shoes and phone and everything else and everyone laughed.
There is a big difference between a good Bluetooth radio and a a bad Bluetooth radio. I have a Dell Alienware laptop and a more recent Dell Latitude. The first struggles to deliver audio to headphones in the next room, the second send audio through several walls with ease.
The worst thing about Bluetooth is that the 2.4 GHz band is very crowded with WiFi, smart home and other protocols. They'd be afraid to demo a cheap tablet with a cheap BT mouse and keyboard at CES and will demo a nonsensical "convertible" or "2-in-1" instead because it won't be clobbered by all that interference.
Other than that, the 2.4 GHz band works very well, if Bluetooth migrated to 5 or 6 GHz people would complain more about reliability unless we also installed more elaborate antenna arrays on the "base stations".
I'd like to see an infrastructure mode for Bluetooth which works like a cell phone or corporate WiFi system which could pipe audio from your TV to headphones anywhere on the grounds, provide dialtone, sync fitness bands, service sensors, etc.
The El Dorado of the industry is millimeter wave which could provide "better than commonly wired" performance over a line of sight but stop working completely if that path is interrupted, by your body for instance. That would need lots and lots of infrastructure to always have an antenna visible to the mobile station.
4.0 and below, yes, iffy. 5.0 and above - better connectivity, battery life, etc. 5.3 is the most current version and its loads better than 4.0 or 5.0.
