The satanic panic was such a WTF when I first read about it. I wondered how the hell so much of the population was actually afraid of a mythological being.
Then the last few years happened and it got hammered home how incredibly stupid and superstitious so many people are.
I grew up in the Bible Belt during the Satanic Panic. It was crazy, the news loved covering that shit.
When I finally got into D&D during the late 80s, even my not-very-religious mom had concerns. I told her it was all just pretend & she watched a session for about 30 minutes before getting bored.
Some people actually believe in Satan, and fear “Satanic cults” on that basis.
Some people don’t believe in Satan, but do believe that baby-sacrificing Satanic cultists exist, and are afraid of those.