@Kamelpov Well, the thing with Kaguya wants to be Confessed to is that, firstly, the author is clearly very smart about how he writes. And secondly, he...doesn't really write his characters as geniuses so much as idiots.
They're book-smart, for sure, but any mind games we see is just an exaggeration of any teenager that overthinks their first crush and any feats of intellect they display can be done by anyone with planning or practice.