The custom audio solution that Sony is using (PlayStation Link) is almost certainly going to be over the 2.4Ghz band as well and I don't see it being any better on battery life then Bluetooth is, which is not that much as the drain on battery from maintaining an active Bluetooth connection is tiny. That being said most users should connect over 5Ghz for WiFi as that would offer a much better experience then 2.4Ghz, in addition Sony can just offer the option with a warning message so the consumer is informed of any issues that might arise from Bluetooth and 2.4Ghz WiFi interference.
Dude what are you saying, please go and research about high bandwidth isochronous data traffic because here we don't want ignorant people.
Nevermind that almost every mobile devices in this world between pc, laptop, tablet, smartphone has a wifi + bt chip.
Playing the portal on WIFI6 while having BT on would have literally made the experience so laggy and stuttering that would be impossible to play anything, if not literally make the device exploding in your hands.