Pinterest is definitely an expert level content farm. For Google Image Search in particular, you're right that it does create a bit of a broken end user experie

Pinterest is definitely an expert level content farm. For Google Image Search in particular, you're right that it does create a bit of a broken end user experience that feels a bit misleading. It's surprising that Google hasn't cracked down on this yet or dealt with the obvious dupes problem (showing image result from Pinterest that came from website a vs showing result from website a).