Have you been in academia lately? STJs thrive there. Memorizing passages verbatim? ISTJs. Memorizing page numbers and who said what in footnote 33? ISTJs. Memorizing facts? ISTJs. Academic work is 99% memorization and organization. You organize your research, your notes, your books, your articles, your citations. Writing a publishable article takes months of steady, meticulous work; writing a book takes years. All of these things are STJ areas of strength.
In all honesty, any type of person can have high academic intelligence. My adviser, for instance, was an ISFP (who is a sonuvabitch, but I digress...) If we're going to go by the strengths of types in general, though, and not of individuals, I see no reason why STJs would not have an equal if not higher level of academic intelligence than most types (even NTs.)