I am still struck by the idea that large media interests would like to eliminate low-cost competition by using downstream liability as a way to end "free entry".
The video above (2 years old) is instructive. It mentions "digital fingerprint technology" as possibly part of the solution. But the Viacom side insists "you cannot have a business model predicated on copyright infringement" (e.g. MGM. v. Grokster, settled 2006). It claims that YouTube knew that copyrighted material was a draw, but much of this dates to before purchase by Google.