Agreed. First Blood (the Rambo film) was also book based. And the Princess Bride.
I could be mistaken but off the top of my head it strikes me that much of the prestige, art films are generally based on something while it's often schlock, lower grade movies which are wholly original.
At least until we get into stuff like whether Terminator or Indiana Jones were ripping off other works.
Maybe we should kill all humans just because you all make things so messy.
I've been pondering this dilemma, partly because I don't like disagreeing with my favorite murderbot, but mostly because I understand why something like Twilight
feels different than something like The Godfather, and I think I figured it out (beyond the obviously different audiences each one was geared toward).
When something like Twilight or Harry Potter becomes a movie, it's entirely expected that it's going to be not merely a film but a multimedia franchise, with video games and online components and amusement parks (if it's big enough or owned by Disney). The first step, of course, is multiple films: you're not just going to do book one of
The Self-Insert Who Got Doubleteamed by a Hot Vampire and a Stud Werewolf, you're going to do all five books, with maybe a prequel or two and maybe splitting the last book in two (or three!) parts. It's expected at this point because of the success of Harry Potter and, sad to say it, Lord of the Rings. But this is a recent-ish phenomenon: plans for multiple installments usually fell on their face until Lord of the Rings managed it. Look no further than '89 Batman, where they laid the groundwork for Billy Dee Williams as Two-Face only to have that crash and burn. That was no simple cameo or shout out -- he was contracted to play Harvey Dent/Two-Face in any sequels, and when they cast Tommy Lee Jones in Forever they had to pay Williams off anyway.
Hell, just look at Lord of the Rings itself -- the 1978 cartoon is billed as Part One, but Part Two never materialized, unless you count the batshit insane Return of the King cartoon ... and you really can't, because that was different people making it, a different aesthetic, and did I mention it's
batshit insane?
And sometimes these anticipated franchises
still fall on their face. Chronicles of Narnia has been stuck at three installments for, what, 15 years? I think there's even a new attempt at it being made now. His Dark Materials made it all of one film and has already been remade or is about to. A Wrinkle in Time, The House With a Clock in Its Walls, and The Dark Is Rising are all the first installments of multi-book series, and all of them are dead in the water right now.
Anyway, just food for thought. May your logic circuits never falter and kill us all.