More pictures of obscure metro stations. Pierre W Major was the architect and the only other thing that he built that I can find online is the Saint-Justin Church.
My best guess would be that he kind of liked (or maybe was one of) Les Plasticiens even though it was built in the 70s.
It appears that Michel Dernuet (who gets all the credit for the piece of art) actually paid the rent by working as a movie art director. That could go a long way to explaining some things.
I like the word frustum.