i think the mistake that people make here is that they don't differentiate types for ignorance. the total ignorance ramains the same until you learn that. in this case scott is just saying that we become aware of our ignorance.
what he is referring to is Unknown Unknowns become Known Unknowns. being the humans we are we are blissfully ignorant as long as they stay Unknown Unknowns but the moment they become Known Unknowns it bother a few while it excites a few.