The tailscale client should have created an interface, but I've never used it on a box also running wg. You don't have a tailscale specific interface in ip addr show at all? That's.... odd.
Relay "ams" means you're using tailscales DERP node in amsterdam, this is expected if you don't have direct connectivity through your firewall. Since you opened the ports that's unusual and worth looking into, but I'd worry about that after you get basic connectivity.
So to confirm your behavior, you can tailscale ping each other fine and tailscale ping to the internal network. You cannot however ping from the OS to the remote internal network?
Have you checked your routing tables to make sure the tailscale client added the route properly?
Also have you checked your firewall rules? If you're using ipfw or something, try just turning off iptables briefly and see if that lets you ping through.
I personally hate all the reddit cross post stuff, and it seems like the majority of lemmy users do too. I don't understand why people obsess over this as a way to "grow" lemmy.
It doesn't contribute to active conversations, in fact it deters users who reply locally and then never get a response.
Just let lemmy grow organically by making good content and contributing, stop forcing it with mirrors from reddit.
I wonder if we could get the top admins to threaten defederation with any instance that doesn't flag automated posts as bots. This way at least the users have some visibility.
Self hosting email is even more of a pain.