Earlier quoted context omitted.
That's not a sufficient answer. The claim assumes that copyright and patents are proven to be beneficial, measurably better than the prior situation. Are they? If so, how? Not to mention, is there any proof there's no better solution?
I think you're moving the goalposts quite a bit here! The original assertion does not assume that the current implementation and interpretation of copyright law is, as you say, "proven to be beneficial, measurably better than the prior situation." The complaint was that "that's not how facts work" but the statement in question was in fact verifiable. If you want to provide proof of a better solution, go for it. Proof…
Forever unto me, the tuple (Int, Int) shall be mine.