It's crazy to me that a significant number of people know "cos" and "sin" primarily though CSS. Is that really what this is implying? Or maybe people just find them hard in general, but it seems odd to think of them as features you dislike, rather than attributing the dislike to the underlying math, if you've ever taken a trig class before.

I take it as the second assumption, as in people who think "CSS has already gotten too complex, now this complicated trig shit is part of it too?".

Keep in mind it's only 9.1%, or 1 in 11, that actually had a "negative opinion" of it. This makes the phrasing/focus on "hated" seem a bit forced.