That will have a non-zero effect, but it's far from the whole story.

Because cars in the 90's weren't aerodynamic? There's been improvements, sure, but most cars then still had pretty good coefficients of drag.

But sure, blame anything except climate change.

This but unironically coupled with about half the total insects we had back then.

Yeah, I've also got the nicest of old cars there ever was, a Suzuki SJ - that is not it.