I see nothing wrong with "lending a movie" to someone.. But how often does the "lent" movie ever get "returned" ( read: deleted )? If not your analogy breaks down and it becomes the same as physically copying a VHD/DVD/CD.
Back in the dvd days, I would frequently never get discs back. The few times I’ve loaned a file from a digital file I’ve bought on Amazon, I’ve never watched the movie again. So for all I care, they could keep it forever.
In terms of digital goods writ large, there is no good way for me to lend access in a provable manner -- so of course piracy is the natural evolution because that's the only way to lend things.
Also, we used to copy Blockbuster tapes too, which is illegal, but there was never enforcement because we never re-sold these copies. Maybe I'm just a miscreant through and through. Irrespective, this is another clear example of where the transition to digital caused a dissonance between the physical and digital worlds that led users to believe behavior called "illegal" was actually just a subtraction of their ownership rights.