I think I might have been even pathologically protective of my privacy in the past, but yes.
As a kid (< 7 years old), I stopped playing out loud if somebody else came to the room where I was playing.
Nowadays I stop doing what I am doing on the computer if somebody else might be seeing it. It's a reflex.
I can't recall any memories from ages younger than 7 that would explain why I would have the need to be so secretive. Perhaps it's because my thoughts weren't generally appreciated so I liked to keep them to myself? I used to ask questions a lot as a kid and usually didn't get any answers. At some point, I stopped asking them and kept them to myself.
It's easier to retrieve memories from ages older than 7 when my privacy was violated. My stuff was searched and letters opened. That must have affected somehow. I had a phase of selective mutism about at the age of 13, to control my privacy.
Also, I've thought about that perhaps the Ni has something to do with how much I value privacy. With Ni, it's easy to draw assumptions even from the littlest piece of information. My mind is drawing connections all the time, some of them more possible than others. If you have that ability, you can't know if others have it too. Even "safe" information could leak/imply something else that you might not want others to know, if you know what I mean.
How this shows in practice: I tend to think others "know" more about me than they actually know. I'm super-surprised when they don't draw the connections that I think are obvious. Even sometimes when I've thorough explained something about myself, people still won't understand it in action. They might ask me "why did you do that?" when I think it's obvious, according to what I've previously told them, why I did it.
The only conclusion I can draw is that most of the people aren't really that sharp-eyed nor even really care that much than what a paranoid person might think. Even if you told your dirtiest secrets, people might not remember the next day. It might be just you who gives them that much weight.
But then again.. there will be those people who know what kind of a person you are from watching you in the eyes once.