Whatever killed the dinosaurs was QUICK, MASSIVE and LONG LASTING.
In certain areas, massive piles of dinosaur fossils are found all jumbled together in one huge formation, as if they had all been washed away in a catastrophe so powerful that they could not stand or run away from it. And these animals were huge, powerful beasts.
And in other places, dinosaur footprints are embedded in stone, that was once mud. As if the dinosaur footprints were never exposed to weather or any type of erosion immediately after they were made, IOW, the place became frozen in time, for millions of years.
And other places, fossils, large and small, are found intact, as if no scavenger ever touched the rotting carcasses after their death and no weather ever dislodged the skeleton’s bones after the flesh was gone.
So whatever happened, happened in a flash, and caused the entire earth to basically stand still for a million or so years..................
And not for the first time, nor probably the last. Later known large impacts were not as massive as the K-T event, though, apparently.