Interesting post. I would definitely not characterize it as "unfilled space". The opposite is closer to the truth for me.
I think skylights is referring to the distance between the persona people see vs who you really are at the centre. I think there's plenty of stuff there if people would like to see it, but I do agree that because we don't fill in a lot of the blanks for people, they assume that there's empty space there that fill in with their own (sometimes erroneous) information.
Somebody said something about feeling a little bit badly that others don't place the same important on accurately understanding us as we place on trying to accurately understand them. [...]
Some types reside near the surface of themselves (I don't mean they're shallow. I just think that you see the real essence of who they are more immediately).
yes, yes, this is exactly what i meant. not that there's not interesting stuff about you there, but that it takes a lot more effort for an outsider to get to your core. i didn't mean to come off as offensive or negative. it's just that my perception, as an outsider, is that there is a lot of "territory" for me to cross before i really know you - to me it seems "unfilled" because i have to fill it in for myself or it's just totally unknown. but i suppose it's less "unfilled space" and more "uncharted terrain". it's just hard to get to really know you. and for many people, instead of making the effort to do so, they assume things - and to some extent we all need to assume a little bit because we have to make certain decisions about how to treat you when we interact. we have to try to make guesses. and some people assume that what they see is what they get... even when they're hardly even seeing your first layer. i'm sorry if i came off negatively, annwn, that wasn't my intention. i figured it would be interesting to hear an outsider's perspective.
i actually relate in some ways because even though ENFPs are very up front about who we are in some ways, there are a lot, lot, lot of facets to ourselves. so people think they know us, but they only really know one side of us. it can be frustrating. but like in the example of the OP, i think it can be rather fascinating too. i don't know as many INFJs as ENFJs IRL - only a few i am REALLY certain of - but i am really drawn to NFJs precisely because of this perceived distance. forbidden fruit syndrome, i guess. it makes me really curious to know the real you. but i also tend to mess up around you a lot because i don't really know how to behave... i just find out after i mess up lol
but as for the OP's questions, yes, i feel like INFJs are different because of this perception on my part, and i do react to INFJs a little differently than to most (but that's really only based off those few people i know IRL). personally, i feel like am more cautious and more approval-seeking. i think it's easy and very pleasant to make acquaintance with an NFJ but much more goes into being their friend, INFJ in particular.