Being blunt, unless a movie contains some kind of twist or unusual story methodology, spoilers don’t spoil anything, unless one makes them do so.

For most movies, everything is going to be just as enjoyable seeing it happen whether or not you know what’s coming. If it isn’t, then there a good chance the movie isn’t that good.

Hell, even with movies that have serious twists, like Memento as a perfect example, someone can tell you what they saw from front to back, and the movie is still going to work because it’s just that unusual.

We watch all kinds of movies based on books, comics, tv shows, even songs, and enjoy them despite knowing not only the ending, but dang near every detail along the way. LOTR? C’mon, anyone watching the movies for the first time that doesn’t at least know about Gollum existing and that the ring gets taken to be destroyed hasn’t paid attention to anything fantasy and pop culture related, ever. But it’s still an incredible ride, even when you’ve read the books, seen the old animated movies, etc.

And even good movies rely on tropes so often that we can predict the ending of most of them in the first fifteen minutes.

Spoilers only spoil stuff if the person insists on it doing so