
My prevailing theory is it creates a hypotenuse that makes their hypotenuse-leg look longer and your brain generalizes tgat impression/illusion to the other obliquely (and therefore: skinny-er)?

My prevailing theory is it creates a hypotenuse that makes their hypotenuse-leg look longer and your brain generalizes tgat impression/illusion to the other obliquely (and therefore: skinny-er)?
I’m having trouble imagining what you’re referring to. Have an example?
I added a not extreme example of it (not 45° but still diagonal)