So the "tcp: fix incorrect undo caused by DSACK of TLP retransmit" done five weeks ago for the Linux kernel didn't need to happen for the Rust implementation?
I don't think this commit has anything to do with wireguard. It's a fix of a bug in the kernel TCP stack, which wireguard doesn't use. (Beware, the wireguard-linux repo is a "fork" of the complete linux kernel)
And even if it did, a userland TUN implementation of the wireguard protocol probably doesn't have the same bugs as the linux kernel one.
And even if it did, a userland TUN implementation of the wireguard protocol probably doesn't have the same bugs as the linux kernel one.