A significant portion of piracy is opportunistic as far as I’m aware, in that people say “well, since it’s free I’ll grab it”. The opportunity cost is effectively zero.
What I’m getting at is that if you have 100 people who pirate the film, perhaps only 5 of those might have been willing to pay to see it, if only there was a convenient opportunity to do so. No money was lost through the other 95 - their decision was between ‘pirate’ and ‘don’t watch it’.
Of the remaining 5, yes, it’s lost revenue, but that’s because there likely wasn’t a convenient service with no ads at a price where people think they’re getting value. It’s all about convenience at the end of the day - if it’s more convenient to pirate it then your service is going to suffer. You have be more convenient.