Haleivi, where does the taz connect shaar chochmos to what you’re referencing (it’s the rashbas ban on young people studying secular studies)? He just says that it’s assur to learn bekevius shaar chochmos and lists kabalah among them. He’s indicating that there’s a reading of kabalah which is not limud hatorah, which i think means if you’re reading kabalah seforim without being muchshar as a mekubal. If it’s for mussar then it’s a different story, as noted.
Where’s the trickery? I think you’re putting more into the taz, i.e. that he’s referring to the rashba without mentioning age or him at all. All I’m doing is saying that since kabalah is Torah, there must be some sort of way of reading it which would merit it being listed with science and math.