Article 13 Is Back On: Worse, Not Better
HackerNews with Turnitin/Copyscape would be far worse than what it is now like.
Really, there are just a few companies which can implement a "copyright" filter.For text:  *Copyscape
  *Turnitin

For the rest:  *Google+Amazon+Apple (ContentID)
  *Microsoft+Facebook+Netflix ("Microsoft Rights", anyone?)