As I said on another comment, my use can be tracked by volume and timing, but since I'm only connecting to my house or my in-laws', and using an exit node on one of them, I'm not doing anything with it that I wouldn't do openly from my house. If I were hosting Anna's Archive, it would not do.

As noted by others, Headscale works if you want fully self-hosted. The features it doesn't have aren't important to the typical home user. The free tier of Tailscale is really, really easy to set up and a very non-technical user can just use it if someone with even modest skills, like me, sets it up. That's why I use it. I can talk my wife through how to use Tailscale over the phone. I can set up OpenVPN or Wireguard (I set up an OpenBSD firewall and NAT system in the mid-late 1990s for an office and used it with SSH tunnels and VNC to do some remote troubleshooting), but I can't troubleshoot it remotely with a nontechnical user.