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.
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.