Pinterest does a whole lot specifically bad - they tend to trap users with login prompts on entry and make it impossible to see the full image. If I'm searching for a meme to DM to someone or a photograph of a landmark Pintrest is something I avoid like the plague. It's essentially a black-hole for images - people pin them and then they are lost forever.
I like Pinterest, it is a useful site. But it is basically a (image) search engine itself, so it's pages shouldn't be in Google results. Just like you don't want Bing or DDG image search results showing up in Google searches.
Pinterest could simply tell robots to 'noindex,follow' the page to help search engines understand there is no utility in it appearing for a search. But agree, perhaps it shouldn't rank first anyway.
Guess it depends on whether it's UGC entirely or whether the CMS could note these kind of pages. Again, shouldn't be hard if it's just a simple link as the main content of the page.
There's precedent that would make it in Pinterest's best interest. IIRC Google's "Panda" algo update basically wiped out search referrals to certain content farms overnight, can't recall specific examples but there were some at the time. They were labelled as low quality and subsequently faded into obscurity.
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EHow is an example of a site that was flagged
