math students are usually pretty intense, but i think it would be unfair to lump them in with the rest of the stem majors. way lower proportion of "utilitymaxxing" chuds because pure math is fucking useless for the century you're developing it in (usually (at this point in history anyway)). on the other hand, i'd add philosophy to the skip list. lot of debate perverts and analytical philosophy wankery at the upper levels. taking intro philosophy courses is very fun though. you are correct about physics being a pretty chuddy/liberal program usually. although the grad students are a mix of interesting weirdos and future war criminals.
the pre-med students are always annoying

source: math and physics bachelors, most of a philosophy minor, most of a physics phd