You're right; my explanation was drawn from many PUA-types who had said similar things, but this effect is perfectly possible in non-sexual contexts, too.

There's actually little use in using words like "stupid", anyway. What's the context? How intelligent does this individual need to be do what they want to do? Calling people "stupid" says "reaching for an easy insult," not "making an objective/instrumentally useful observation."

Sure, there will be some who say they'll use the words they want to use and rail against "censorship", but connotation and denotation are not so separate. That's why I didn't find the various "let's say controversial, unspeakable things because we're brave nonconformists!" threads on this site to be all that helpful. Some comments certainly were both brave and insightful, but I felt on the whole a little bit of insight was brought at the price of a whole lot of useless nastiness.