One would think so but I've scored as both in MBTI depending on which test and perhaps my (mis)interpretation of the questions. I don't see MBTI as having much of a future except in pop culture; although it does demonstrate a valid aspect of third-party perception of function, I haven't given the system very much attention. Socionics is salvageable even though its descriptions lack the aspect that MBTI demonstrates........
a.k.a. I/O