I find INFJs to be rare. They are the one type I couldn't personally think of a real life example. That is, until I one day figured out I'm one myself. That was hilarious. Since becoming aware of my cognitive set-up, I seem to be able to spot other INFJs. It's pretty obvious when you get to know them a little. They're rare, but they exist. Usually, they seem drawn to certain areas of insterest outside of which they appear mostly absent.
For me, being an INFJ means being misunderstood, and for a long time, not even understanding myself.
I think what creates such a chasm is the Ni dominance. Ni is so removed, seemingly not relatable to other persons who don't have it. I perceive a big difference even between Ni dom and aux users. The aux users I know seem grounded in conventional reality; it is their base. My base is space; it is where I'm grounded. The only thing that prevents me from taking off into space completely is other people (Fe) and physical activity (Se). It's definitely a struggle, though. I do not want to be here most of the time; I'd like to be somewhere else and every now and then come back to visit. I think that's what I'm already doing. Lol.
I tried to disclose this to a few other people. It usually earned me confused disbelief ("What?") or worried disbelief ("You have a problem."). I've stopped trying to explain myself as a general rule.
Being a rare type is one thing (ENTJs are rare; so are ENFJs). Ni dominance is is another. Would I feel out of place if 20% of the population were Ni doms? Certainly less so, but I'd still be an alien in this physical world; and I'd still feel worlds apart from the other 80% of the population.
Just to make sure: I do not believe Ni is "better" than any other function.