It's not just identifying with some vague general points of the description. For some people reading an INTP profile for the first time is blow-your-mind-and-shit-your-existential-pants amazing.

INTPs would be first in line to understand and point out the kind of cognitive bias that make people believe in horoscopes and astrology (and possibly the other 15 MBTI categories).

Care to share what is so amazing about it? As it apparently describes millions of people to a T :/

That's why horoscopes and fortune cookies work.

Except in bed.

Interesting, but somewhat unsatisfactory, I feel. What if the description really did describe everyone quite well? For example "you are a human" would describe everybody quite well. So the experiment seems incomplete.