Check out NetBSD mailing lists about NB wireguard. Same kind of story, but NetBSD maintained they had a quality implementation.
http://mail-index.netbsd.org/tech-net/2020/08/22/msg007842.html
As an outsider I got the strong feeling that the only issue was that Donenfeld was not involved in the port. He hinted about many issues, but did not seem.to give a single concrete example.
No idea what happened about the meeting the participants agreed upon.