We don't mind interacting with interesting people. In fact, we like that a lot.
But in a social setting where you have 5 or more people, at least one is going to be someone you wish wasn't even in the same converation with you.
If it's nerdiness, it's almost a snobbish nerdiness, except that there's no desire to exhibit it. We'd rather just avoid the situation from happening in the first place.
That's introversion, but it's not caused by being shy.
in other words: NMSD - "not my species, dear"
that's rational analysis (thinking and judgement), not emotional weaknes (shyness)
Spoken like a true INTP. LOL!