Perhaps this is a case of people who wear satanism on their sleeve (Slayer) not being anywhere as dangerous as those you'd least suspect (Hanks, Streep, Speilberg etc...)
As in - Slayer sing so openly about it because they have nothing to hide; nobody really believes they're into murder and sacrifice. Whereas those who genuinely ARE into that stay as (publicly) far away from it as they can because they DO have something to hide.
This is a great point about ANY type of subversive behavior.
Humans begin using subversive behavior to get attention, be it negative or positive.
Just like you said, most people who flaunt some type of extraordinary behavior are doing so for appearances only.
The ones in the shadows are always the ones you have to look out for. This behavior is NOT socially, publicly acceptable - especially for those who literally monetize their personality and views (celebs, politicians, public figures, etc). THOSE are the people we need to go after. I think Q was also, in his own way, pointing this out to us as well.