It's a fun "oh wow what if" theory, but ultimately falls apart under any scrutiny.
A few gaping holes:
-If "a bug's life" takes place post Wall*E in an apocalyptic Earth where only bugs and a relative handful of humans remain, where does the bird that attacks Hopper come from?
-Cars can't become the "sentient machines of the earth to replace humans" because in the world of Cars... there's nothing human to replace. Everything in the world of those films is based solely around the needs of the automobiles; there's absolutely no remnants of any human world that proceeded it. And the apocalyptic world of Wall*E (post Cars) would reflect a world devoted to automobiles, which it doesn't.
-I don't buy that monsters came from animal-human interbreeding/mutations. (Again, where are the other animals besides bugs coming from?) I think we'd have some indication that the Monster world was once the human world if there was any sort of intention like that. (Granted, I'll admit the time travel mechanic they're talking about here is really neat & thought provoking.)
-Why does "Boo" as the witch from Brave settle in medieval, rural Scotland? Why not anywhere else even slightly more exciting? Again, I'll give the writer credit for a clever connection, but the obvious question remains unanswered.
-This does not actually
explain the wisps in Brave (instead just saying they're the source of
everything), which appear to be nothing besides inherently magical beings.
Agreed that the writer just likes to create stretched connections between Pixar easter eggs. It was a fun, creative read, but that's about it.
