The issue I have with tailscale/headscale is that its focus isn't being an end user app that people can start on demand.

Hamachi was different because a child could use it (literally). It was designed like an instant messenger, and you could easily create groups and invite friends for a LAN party. No IP masks, no hashes, none of that complicated stuff was necessary.

I'd only see maybe a tool that was built on top of headscale that could do that, but headscale's focus is too far off for something like that, and in my opinion too low level.