Not the way I was thinking off; I was thinking more along the lines of brain atrophy until humans are helpless (maybe 2 complete generations of humans).
And that's a short extinction; the KT extinction took place over thousands of years. If, 1000 years from now, we are finally at the place described in "The Machine Stops", only then will an observer be able to decide that we don't have the necessary critical mass of intelligent humans anymore.
Humans got to be the apex predator simply on intelligence alone. It's possible that without thinking ability we'd go extinct.