One fun thing about watching a fuckton of movies all the time is I'll be watching some random old thing and slowly realize a classic movie took heavy inspiration from it. These are the ones I've stumbled across:
Hatchet for the Honeymoon (1970) -> American Psycho (2000)
Poor Little Rich Girl (1917) -> Wizard of Oz (1939)
Burnt Offerings (1976) -> The Shining (1980)
It would be cool if these older films were actually better than their famous descendants, like how books are usually better than their film adaptations, and original movies are usually better than their remakes, but this is not the case. At least for these three examples, the classics deserve the hype and the older films are elevated by the association.
It is a cool experience to identify some visual or conceptual similarity, and then see more and more similarities as you go, especially if the themes and ideas behind these images are very different. For example, the dream in PLRG is visually similar but much scarier than the dream in Wizard of Oz, because you're aware that she's in great danger from poisoning. It is a more melodramatic situation, told in a less ambiguous style (this is very much the case for all 3 originals).
I love comparing how different actors treat the same role, especially if I can get a contrarian opinion out of it (Ricardo Cortez' Sam Spade > Bogie's). It is especially striking to compare Oliver Reed to Jack Nicholson in the role of "scary dad." Nicholson is much creepier, but Reed is arguably scarier as he is so physically imposing and goes in and out of self-control. Certainly his death is scarier.
I suppose the main thing I'm trying to get my head around is this idea that classic movies are incredibly influential, but they themselves are not original sources, just better ones.