Lots of basic human enemies late game have...

a) insane ability scores like multiple 20's and the rest in 14-16 range
b) homebrew "armor" buffer abilities that you have to break through before you can do anything to them (Hello, DOS)
c) Magic Resistance for no reason other than to have magic resistance to screw spellcaster PC's and turn them into lame magic missile machines

Jeez how much they hate control, spellcasters and tactical combat other than grinding away at big HP pools and armor buffers.