In film after film, the basic rule seems to be that composers avoid displaying any trace of enthusiasm in their music. A certain detachment from the material is essential.
Take a 70s TV scene, such as Fonzie jumping the shark, and you hear the difference right away (notice, by the way, the cute homage to John William’s famous 2-note motive from “Jaws”, in the lower brass):
Audiences today have been so overexposed to media that they’re hyper-sensitized to storytelling conventions. So if you make the mistake of saying too much in the music, you’re insulting them, so they just think you’re corny.
That’s not a bad thing by any means…I myself feel distracted by hyperactivity in old film scores, even ones where the music is clearly a masterpiece.
(Ironically, the music from Jaws, also from the 70s, doesn’t sound the least bit dated at all…)