Just keep reporting the nudity that you find offensive. I guarantee, you're not the only one who's thinking the same thing.
The other thing I would do is, I would write an email to them. I would just tell them my thoughts honestly, and that "you find it disconcerting, unpleasant, and obnoxious in an otherwise enjoyable experience, that it hasn't always been this way, and would they please consider making changes back to the way it was, or you will just have to spend your time on other websites with similar content where they haven't introduced nudity."
Here's where you can go to report your concerns on Facebook: https://help.pinterest.com/en/contact
What I don't understand here is, between you and me, nudity is something that attracts men, not women, and Pinterest fans are mostly women! We would rather find that next best recipe for removing gum from carpet (or whatever our interests are) than we would enjoy seeing someone nude....especially a nude woman! I'm speaking to you as though you are a female, I hope you are, or I need to apologize for assuming something!) I might mention something along those lines to the company as well, that it just doesn't make logical sense to you.
You may have to report your concerns several times to them. But keep in mind that feedback from their audience is how they learn what is working for their viewers and what's not, and they are dependent on your feedback to help them keep their website vital and popular among the people. You're not being an "ugly" person, or complaining just because you like to or have nothing else to do, or that you're a "bad" person for not liking what they've introduced. No! You are offering feedback to them as an audience member, and they want to hear your feedback because it helps them.
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