Having studied literature, I was taken aback by this, as it really is a nice story, that fit the facts after the fact. It is the classical "post hoc, ergo proter hoc", that is so common in (at least German) literature science. Some small factoids are taken from "texts" (or here movies) and over them a nice story is fabricated, to "explain" these factoids. For example the timeline. Does Cars for example mention the ti…
Actually, the problem is not a lack of explanatory power, but a lack of predictive power. If Pixar comes out with a new movie, is it possible for it to refute this theory? Not really. It's already been demonstrated that if a date is explicitly mentioned, it can be dismissed as using a different calendar system, and the theory doesn't change.
It seems that this dragon is incorporeal, so spray paint won't stick to it.