Who forbid it, and how do they enforce it?
They make crap as they go. Bread and circuses.
“Anne Francis stars in (ooh-ooh-ooh) Forbidden Planet
Wo-oh-oh-oh-oh-oh
At the late night, double feature, picture show”
Science Fiction/Double Feature from The Rocky Horror Picture Show
So I guess it was Dr. Frank-N-Furter who forbid it.