Weet ik veel is a common everyday Dutch expression, so the clip spread less as a quote from a specific show and more as a reusable reaction sound online. Short spoken phrases like this travel well on soundboards and in edited videos because the meaning is clear even from the tone alone. Dutch speakers use it to deflect a question without sounding serious, and that casual, slightly annoyed shrug is exactly what creators borrow when a scene needs a quick, relatable I do not know moment.