Luckily i had created a reverse ssh tunnel on a vps before leaving.
If they are doing CGNAT further into the infrastructure, how would I even be able to tell at this point? I’m assuming someone would also block ICMP just so it would be less embarrassing, but who knows.
Comcast does generally seem to be moving towards IPv6 at least, which is helpful.
Check the IP on your WAN interface of your modem? I mean, that's how I have always been checking for CGNAT.
I've had this problem in the past with Vodafone, sometimes their AFTR (?) would go down but all ipv6 enabled hosts were still reachable. Only the ipv4 internet was unreachable. It took months for me to find that out, and I still don't know any workaround in case that happens again.
T-Mobile is running IPv6-only using 464 which is vulnerable to AFTR problems like you saw.
HTH,
John
On the server side, in contrast, NAT is winding down. 15 years ago, it was common to have either DMZ-style NAT, or on AWS you had to have NAT (they call it EIP). Nowadays, having a CDN or could-native load-balancer in front of your server is increasingly common. And behind those, that server just don't need a public IP (maybe only a shared outboud NAT for OS updates). That is - if you have a server at all (and not moved to lambda, S3, etc...)