Being quiet gets you underestimated. Being quiet and prepared gets you remembered.

Quiet on its own is ambiguous, and rooms fill the gap with whatever they already assume. Add preparation and the same quiet reads completely differently, because when you do speak it is specific and obviously not improvised. One well aimed sentence from someone who has said nothing carries further than ten from whoever never stopped.

Pick the class or the meeting where you want to be taken seriously, and do the reading first. Bring one question or one fact. Say it once, early enough that it shapes what comes after.