The site you gave has a brief history which seems right to me . I remember the cube’s release and it wasn’t when I was 3 years old(1974) , the late 70’s/early 80’s seems right to me .
I don’t remember which year, but their may be enough info between all of us that we can hem it in. I had a friend in college who played with one a lot and he graduated (went bye-bye) in 1978. So, by then anyway.
You know, I think it was popular in California long before it reached other areas. My friend in Carolina tried to convince me it was new ( well after I was done with it) until I showed him 2 kinds in the dusty end of the closet.
It’s the Pet Rock syndrome. Lots of new things get sent here first.