For built in listeners use ncat, but nmap package is not always included. If you are on Windows find some listener Poweshell script, it will be under 10 lines, with Test-Connection. When I was a SysAdmin one repeated problem was UDP traffic was not working. When you tested the TCP port it would work, verifying that the connection is there, but UDP for a variety of reasons is problematic.
With TCP there are built in listeners on OSs which you can use to test. Also TCP will work before UDP. For whatever reason firewalls and such do weird things with UDP traffic. I always use a cli tool that I can’t remember the name of for testing.
Yes it is uncommon, as people have mentioned it is a Wireguard wrapper. Try just using Wireguard and troubleshoot from there. I would want to know what that ‘simple’ solution is failing. Your workaround could have similar issues.
I always thought that people are drawn into the default instances because they have less friction to sign up and login in third-party apps. Along with new people not quite grasping how the fediverse works when they start using it.
I was using a etke as a hosting service for a while but it was a bit expensive and I wanted more control. I set it up on my homelab with a VPS running a reverse proxy and like it a lot more. I believe I deployed it with someone’s Ansable playbook I found on github. Make a matrix.org account and play around with it. I hate the Element client though.