Most large industries have regulatory bodies or rating systems which aim to keep power where it lies. I recently watched Kirby Dick's This Film Is Not Yet Rated, a film about the MPAA ratings board.
The MPAA ratings board is composed of what is deemed as typical moral parents, but they play up to support large movie studios. If a film is rated NC17 some studios won't release it, and even if they will it is hard to advertise the movie.

Matt stone, one of the creators of South Park, mentioned that when he tried to get an independent film reviewed they gave it a NC17 rating, and would not say why because they said if they gave specific reasons they would be practicing censorship. Later on he got Team America reviewed, and they gave him a laundry list of what specifically needed to be changed to avoid an NC17 rating.

Some of the absurdity of the movie ratings game include the likes of good ratings for violence in movies (especially without blood), but non missionary sexual intercourse is not proper. The support for violence in unsurprising given the absurd number of movies that run military ads prior to starting the film. The military is not only a leading advertisers, but if a producer needs military stuff to create a movie, the pentagon has to view the film before public does.

Virtually every large market has some form of censorship / reviews board. The stuff they censor is likely a large market waiting to be tapped. If they are unwilling to target those markets because of fear of blowback from advertisers that presents a large targeted audience and strong monetization strategy for independent creators.