> VoLTE with fancy compression didn't make audio quality better, it just freed up bandwidth for carriers to cram more channels in.
Not just that, it’s also used for additional carrier lock-in!
(In Canada, carriers were barred from selling carrier-locked phones some years ago, but since VoLTE, they don’t support VoLTE functionality on any phones that haven’t been certified for use on their network, which is limited, in practice, to phone models that they sell themselves. Normally this means you fallback to 3G for calling, unless you happen to be roaming with a carrier/country where 3G service has been dropped, in which case you simply don’t get any voice service.)
Not just that, it’s also used for additional carrier lock-in!
(In Canada, carriers were barred from selling carrier-locked phones some years ago, but since VoLTE, they don’t support VoLTE functionality on any phones that haven’t been certified for use on their network, which is limited, in practice, to phone models that they sell themselves. Normally this means you fallback to 3G for calling, unless you happen to be roaming with a carrier/country where 3G service has been dropped, in which case you simply don’t get any voice service.)