Critics absolutely hated Sabbath. If and when they did get played on the radio, its was always 2 songs, Paranoid and Iron Man. Warner Brothers didn’t “promote “them very much. Unless you were a hardcore fan, nobody really knew the members names. When Randy Rhoads was called aand asked if he wanted to auditiion for Ozzy in 1979, Rhoads asked “WHO?”...they had to explain who Osbourne was. Rhoads at first politlely declined the offer...he HATED Sabbath. You are right, they were a “cult” band. You either loved em or hated them.
I must admit, the only thing I knew about Sabbath came from a Cheech and Chong routine.
“Well once I played Black Sabbath at 78 speed, man.”
“And then what happened?”
“I saw God!”
“You saw God, well that sounds like true spiritual enlightenment to me, Bob.”