My father, Chuck Hastings, worked at Monolithic Memories (MMI) in the early 1980s.
One of his co-workers, David Wyland, mentioned the Law during a presentation. (I presume he did not title it "Wyland's Law" at that time.)
My father thought the Law was worth remembering, and taught it to his kids. My brother, Steve, quoted the Law when he posted a comment on Jerry Pournelle's website.
IMHO, Wyland's Law should be attributed to David Wyland.