It would have been nice to see a bit more on the technical side. For example, with WiFi calling, the call is encrypted in IPSec as mentioned, but also encapsulated in UDP. This enables the traffic to pass through NAT, etc. My understanding is VoLTE calls are also encrypted, at least over the radio link, but I don't recall mention of that. One other thing that was hinted at, but not mentioned is this travels over IPv6, at least in the IPSec tunnel. I believe IPv6 is mandatory for 4G & 5G. My own phone is IPv6 only and uses 464XLAT to access IPv4 only sites.
