https://github.com/n0-computer/pigeons offers the same but with SSH.
I use it in my homelab extensivelly for access, tunneling smb, postgres and some other minor bits.
I'm a big fan of iroh, but I think iroh's holepunching algorithm is at least partly based on tailscale's, so it's not 100% accurate to say iroh got there first. (Just the "as a library without a control plane" bit.)
It's all just knockoffs of Skype and BitTorrent :)
I'm glad there's a competing Rust and Go implementation now. I like Iroh as a Rust user and having tailcat around doesn't hurt me