Hint: don't try strawman arguments, it's not very becoming. I never said content was *calculated* into anything.
Content was *always* the way this worked - not because the content *itself* is scored, because that's insanely difficult to objectively measure. But if you have 100 links pointing to you on a given subject, where there's clearly some contextual relevance, chances are you're more authoritative on a given subject. Ditto if when searching for a term on Google and you turn up in the results and the user doesn't come back to Google for a second opinion, it can be inferred that the content was a good match for the search query. (Google does track this.)
Having good content is *literally* the original way to produce inbound links from other sources, it's been that way forever, and it's been the basis of Google's PageRank since before they were called Google (although there are plenty of other 'signals' now for authority)
As for weeding out copy sites and spam sites, if the same content appears on multiple domains, it's a clear sign that something's a duplicate, the only question becomes whether the little site copied the big one in the hopes of ranking, or the big one copied the little one thinking no-one would care (both happen).