Free project idea for someone with more time on their hands than me:
Classical search engines determine trust automatically, based on various factors including "link neighborhoods" where trustworthy sites link to other trustworthy sites. These automated strategies are clearly breaking down; the spammers are winning the arms-race.
So maybe we need to go back to human-based trust.
People used to curate lists of websites, which partly solved this problem but didn't necessarily scale. I wonder if that idea could be supercharged.
Consider a browser extension that people install, which:
a) gives users a button to mark a site as trusted/favorited
b) tracks domains visited (and frequency)
Then, separately, you can manually add people you know personally to your "network". You trust them, so anything they trust is also something you might be able to trust. Manual favorites could be weighted higher than frequently-visited sites, and both could be displayed inline next to links on all pages you visit. You could also see which people the trust in a given link comes from, in case some of them consistently have bad judgement about these things and you want to remove them from your list. Then, finally, you could create a personalized search-engine that only indexes the sites determined to be trusted by your personal network.
Of course this would require placing a great amount of trust in the extension and service themselves, so maybe they would have to be open-sourced or self-hostable or something (a profit motive might create a huge amount of temptation to abuse the data). That's a stickier problem.
Edit: There was a little ambiguity left here about transitive trust; “friends of friends” type stuff. I think if this went on for unlimited hops, we’d be back at square one. So maybe it only uses direct contacts, or maybe some small N of hops (where longer ones are weighted lower?). Maybe this would be configurable, not sure.
Also re: privacy, maybe you could come up with a clever way to E2E encrypt the site visit data, even though it’s shared with many parties?