It’s not a misconception. There’s no fossil evidence for a decline in the dinos or for a transition to mammals prior to Chicxulub. There have been one or two finds which have been purported to indicate dino survival of the impact, by literally the same folks who formerly claimed that there’s no way to find a sudden event in the fossil record. But even their purported finds show exactly that.
The Great Dying was known for decades, and was puzzled over, because gradualists couldn’t consider the right questions. If the extinction of whole taxa comes about because of impacts from space (or for that matter, worldwide volcanism as Dewey McLain and others have claimed), it undermines the Darwinian view, which is why the rejectionist front (as it were) is rooted in England.
Wow... I didn’t know that.
I stand corrected! Was just difficult for me to imagine something 6 miles wide wiping out most living things on the entire planet all of the sudden like.