Could you please post some examples of search queries (text or image) that are dominated by Pinterest?
I share the sentiment in other comments that search engines are (deliberately?) allowing SEO abusers to degrade the user's experience. I noticed that for some queries (Like "How to brush teeth"), there are more ads on the first page than results! They're marked, but not in an immediately-visible way; I'd be most people integrate them with search results mentally.
I started throwing together a search engine about a week ago to address these concerns, and put it online yesterday. (https://www.pageref.org). I'm deliberately penalizing SEO abusers, and promoting websites that have high-quality content. Running custom searches on these sites in some cases based on keyword.
In a lot of cases, I'm throwing in search queries, and going through each result one at a time, and categorizing them; eg penalizing sites that use clickbait or scammy ads, that are low-quality but show up high in results etc, or probably aren't relevant, but are highly SEO optimized, like Pinterest.