On the other hand, GR's "vision" was dollar signs. So if he had limited the viewing audience with overt adult content, that might have cut into his paycheck.
I think you're making an assumption there based on modern sensibilities, the perception that R-rated movies can't make as much as PG-13 blockbusters because of the smaller audience. But TMP came along just at the start of the modern age of blockbusters, so that perception hadn't settled in yet. There were a lot of R-rated, adult-oriented movies at the time that were successful; the market just hadn't yet been so thoroughly overtaken by the huge blockbusters that dwarfed the kind of profits most movies usually made in those days (aside from a few like
Jaws and
Star Wars, but those were considered less reputable than they are today).
Indeed, it was only when the MPAA ratings system was established in the late '60s that it became permissible for movies to have frank adult content, nudity, sexual themes, and the like. So in the '70s and '80s, that was still a relatively new market that filmmakers were eagerly exploring, which was why we got so many raunchy sex comedies and erotic thrillers and nudity-laden slasher films and the like in those decades.
Pretty Maids All in a Row was one of the earlier examples, and one of the tamer ones compared to what followed. I'm sure Roddenberry would've been glad to be part of all that. He always wanted
Star Trek and his other work to be taken seriously as adult drama. He wanted respectability as much as he wanted profit.
Indeed, we know he walked away from doing
Questor as an ongoing series because he refused to compromise and dumb it down as the network wanted. He chose to give up the money he could've made from the series rather than compromise its intelligence. If anything, that shows he cared
more about respectability than profit.