I use cloudflare to make my weather station available over T-Mobile. They don’t filter inbound ipv6 on regular phone lines (they do for TMHI) so you can host a simple page on ipv6, only set the AAAA record in cloudflare, and they will proxy it for ipv4 users so I can ignore being CGNAT’d for ipv4. Make sure if you do this setup with a tool like ddclient to keep the record current as T-mobile rotates ipv6 frequently