I'm not sure I would call this "solved", since it's effectively just a replacement for the DNS servers in effect.
What I want is no additional dependencies, esspecially on dynamic and slow to propagate services. Not to mention that my current dynamic DNS (through tplink) seems to be filtered by a lot of firewalls or something.
ISPs providing a static IPv6 would be a simple solution that I should be able to create my own DNS records for convienence. No external VPN or otherwise.
Tailscale appears to have solved this problem. There are related open-source projects.