Dubbing hentai is still around today. Kitty Media is the only label in America that keeps licensing old and new hentai with their dubs. In 2019 three more hentai were dubbed.
I feel like people have already been exposed to a lot of subbed anime and have already accepted it as subbed. I remember watching naruto as a kid dubbed and then switching to subbed to get farther in the series. Plus dubbed just sounds worse