The "autonomy" thing is big. You share a bit at a time, testing to see whether people will try to snare you with what you've revealed. If someone betrays you by trying to control you or leverage the information against you, you stop.
Some other types plunge in more quickly and are not nearly as sensitive to "control issues."
It can be argued that the INTP is mistaking healthy connection for relational enslavement, but the inverse can also be argued for other types.
I know that personally I love intimate relationships... with people I can trust to not abuse the information I've given them by trying to gain power over me. If they are willing to go that deep, I am willing to go that deep. In fact, I *want* to go that deep and become bored when someone won't.
Note that "intimate" for me tends to be more about "shared information" -- I will tell you EVERYTHING -- rather than what some other types might consider intimate. IOW, I desire total disclosure, with the promise I will never use the information against you; and I am willing to tell you anything about me.