In truth they can be quite smug and distant and hard to know. With some of them they act like they're doing you a favor by giving you their attention. Depends on the INTJ and how mature they are.
A mature INTJ is warm and wonderful inside, and just measures the world at a distance with calculated logic. A less mature INTJ is kind of judgemental, cold-hearted prick.
Hmmm I don't know if this has anything to do with sensing feelings and intuitive feelings, but rather than they give HEAVY HEAVY weight to logic and we give much more credit to nuance and feeling. INTJs can seem like the Thinkerty McThinkers of Thinkers in terms of being excessively logical. They're sometimes overly logical, and it's obviously to protect themselves.There's a problem that occurs regarding the filtering of information. Intjs' aren't intuitive feelers, their feeling is informed by Se. This encourages them sometimes to dismiss feeling fed by intuition (nf). Just like nf's thinking is fed by sensing and can come at a head with intj thinking fed by intuition.
There's great advantages to this if you can work together as a team. But if you aren't aware of the dynamic described above, you can come to a point of contention. I've seen intjs' describe feelings as black and white etc. You can see the fi+se, which leads to different information filtering from fi+ne for example. Nf scratches a whole other layer of reality, NT doesn't and NT scratches a whole layer of reality NF doesn't. As long as you can recognise the merit of both and among other things, I guess it can work. If you're not very well integrated and become aggravated, confused, bemused by the others' means of coming to conclusions, then it gets tricky.
If we talk about it in terms of function theory, I see INTPs as being more "open" even with their inferior Fe, being realistically less sensitive, and INTJs as being more "closed" trying to protect their little Fi flame like "my precious my precious" with this hard outer shell covering up major Puss In Boots.
Yeah, ENTJs are easier to get to know, or at least at a younger age. Extroverts are easier to crack like that.I prefer entjs'. Simply because I seem to get on better with dominant judgers. I tend to prefer Te as someones dominant function rather than supporting one.
I also prefer intps' above entjs'.