Pretty amazing that you can achieve such a throughput in a Golang userspace program. I wonder if other UDP based protocols like QUIC can attain those numbers as well.
Slack has a system called Nebula that's pretty adjacent to userspace WireGuard.
Nebula is a Tailscale clone
Nebula predates tailscale.
link for the lazy:
https://github.com/slackhq/nebula
Also with no ill intent looks like tailscale has the far more effective marketing organization :)