Going through the trouble of implementing CGNAT and skipping IPv6 seems like a partially degraded service for the end user though. It's becoming common practice for ISPs to slap all the users between two layers of NAT and calling it a day. You can't run essentially anything on your network (not even an SSH server) without having to have a server on standby and reverse tunnels. I know there are not enough IPv4s but at least let me having the option to pay for one. Or, you know, give me an IPv6. Otherwise it's practically a networked content consumption service at this point. It's 2021, the "IPv6 is complicated" excuse must stop at some point.