Casablanca is a famous example of this too.

And LOTR, though in that case coming to it after reading Terry Pratchett was difficult for me (Pratchett didn't just copy its, or other, fantasy tropes, but send them up in an exceedingly clever way).

Yeah, there’s a bunch of these. I really like finding these sorts of “ur-“ moments, the first time a way of doing things really crystallizes into something other practitioners can see. The Matrix is another one - that movie is the transition point from 90s cinema to the 2000s, and it’s a little clunky from a 2000s viewpoint, but if you look at everything that came before it, it’s so clearly a turning point.