Besides that, I looked at every DynDNS system I could find back in the summer. There were only 3 that I was happy with; Hurricane Electric, Google Domains, and a pair of self hosted Bind servers.
If you want the best, simple solution, and it doesn’t need to be completely free, register a domain with Google domains. If anyone knows of limitations, let me know.
Namecheap maxes out at 150 DynDNS hosts :-(
They don’t get traffic going through them. They mainly exist to point to an IP. With enough data they have information on how an ISP rotates IP’s and who they’ve gone to.
In your case, with a WireGuard VPS, all traffic goes through the server. That’s a very different setup.
In their case, a request goes to them at a regular interval and they update the IP the dns record points to. That’s it.
When someone requests the domain, they simply respond with an IP. At most, if there’s little caching, they could get frequency of usage.
A rouge DNS can reply to select queries with the IP of a middleware that can TLS proxy and/or MitM that traffic.
We built such a thing mostly for anti-censorship purposes (bypass IP blocks): https://github.com/celzero/midway#demo
You can keep jumping to new gimmick first year deals on unusual TLDs but they are often considered spammy and always gouge on renewal pricing.
I ended up going for my own VPS with a WireGuard server for my home server to connect to.