I’ll take this question in the spirit of the community you posted to. “No stupid questions” refers to the saying “there is no such thing as a stupid question,” which is am aphorism meant to destigmatize expressing ignorance. This is supposed to be a place to ask the questions you might be afraid to ask because you assume everybody else already knows.

The other posters are responding a bit comedically at the notion that this community is fundamentally opposed to asking “stupid questions” when it’s traditionally been a space for “I’ve been afraid to ask, but are you supposed to use shampoo or conditioner first?” type questions.