[Retric]

Any open voting system is going to be under serious SEO pressure.

That’s the real issue, Google has indirectly infected the web with junk sites optimized for it. Any new search engine now has a huge hurdle to sort through all the junk and if it succeeds the SEO industry is just going to target them.

A more robust approach is simply pay people to evaluate websites. Assuming it costs say 2$ per domain to either whitelist or block that’s ~300 million for the current web and you need to repeat that effort over time. Of course it’s a clear cost vs accuracy tradeoff. Delist sites that have copies and suddenly people will try to poison the well to delist competitors etc etc.

[Nasrudith]

Adding a gatekeeper collecting rent isn't a solution - the people using SEO are already spending money to get their name up high on the list.

[Retric]

This is money spent by a search engine not money collected from websites. People don’t ever want to be sent to a domain parking landing page for example.

More abstractly SEO is inherently a problem for search engines. Algorithms have no inherent way to separate clusters of websites setup to fake relevance from actually relevant websites. Personally I would exclude Quora from all search results, but even getting to the point your trying to make that kind of assessment is extremely difficult in the modern web. Essentially the minimum threshold for usefulness has become quite high which is a problem as Google continues to degenerate into uselessness.