I think there's a great opportunity now for a new search engine that evaluates the general spamminess of a site, and then punishes sites that link to spammy sites.
These days there are more attributes to add subtlety to your outbound links of you want the search engines to take you seriously.[1] I'm sure other search engines make similar judgements based on them.
[1] https://support.google.com/webmasters/answer/96569?hl=en
(One could do this separately for various kinds of undesirable content and let the users choose whether they want to avoid spam, hate speech, plagiarized content, nsfw content, misinformation, Rick Astley videos, and so on.)
There's plenty of room for improvement in search. DDG is already edging ahead because it searches for what I want, not what it thinks I want.