Friend and commenter Jeff, I believe, may have nailed the reason for stupidity's stubborn resistance to eradication:
Stupidity flaunts the Third Law of Thermodynamics through behaving like the mythical perpetual motion machine. I suspect that there is a hidden energy source, but finding and stomping it to death has proved elusive for generations of genuine truth seekers.
Hmmm...hidden energy source...Let's see if we can find it...
"Ok...brain mass measured in milli-bidens times the speed of fake news dissemination divided by Hillary Clinton's average post-election blood alcohol level...Eureka! I think I've found it!"