One of various things I like looking at are the semi-illogical causal events that would prevent the entire narrative of specific movies from happening.

If seahorses were already extinct, Finding Nemo would not have happened. Seahorses are pushy*, trust me. Nemo's arrival on Blu-ray late last year finally got the entire Pixar library on Blu-ray, with no "vaulting" in sight.

*I keep seahorses.