I think it's okay to have some websites where sexual content isn't allowed, but this is pretty fucked up. They have a platform that's been built around user shared content, and a very high percentage of that is sexual content. Now all of that work that people have created will be gone. Or, at least, a lot of links are going to stop working so that really sucks.
But we all know it's for money. The tech industry is entirely built around this model: build something that is actually good and free > Generate lots of users as a result > Reach critical mass and try to monetize > By monetizing, the platform becomes shitty > Everyone shifts to a new platform.