First, the source that said that was just a guy on Twitter who simply had copied someone from PerC that posted a rank of intelligence in order. The criteria was simply just what a random person from there has thought, basically INTJ is the most intelligent because that guy thinks it is.
Second, there are 132809120 studies related to IQ showing that intelligence by IQ has INTP as highest, with a few non-IQ studies showing the same as well.
Third, there are different kinds of intelligence; Although a lot of them will just point to INTP (even if most of times MBTI doesn't end up being a really strong factor), not all of them are like that. Emotional intelligence and IQ intelligence are quite distant from each other; I haven't seen anything using EQ and MBTI, mostly because the definitions of EQ are quite fragile, but some of the EQ tests have F related behaviours, with some of them specially having Fe related behaviours of controlling your own emotions according to what you need, I voted ENFJ just for the 'n' bias, but ESFJ/ENFJ are the most likely to be highest on EQ by the definitions I had read about that many months ago.
