You're right that the group was probably ready to loosen up anyway. It's like the quiet was a stretched rubber band. Any little snap, a dropped fork or a weird joke, lets the tension go. My dumb remark was just the snap that happened. The real change came from everyone deciding to stop being so polite and just talk like normal people.
But was it really your comment that changed things? I see it another way. Sometimes in a quiet group, any talk can break the ice, not just a clumsy one. People might have been ready to open up on their own, you know? Your words just happened to be there at the right time. I feel like the shift comes from the group wanting to relax, not from one person's remark.
That rubber band idea is spot on. I was at a work thing last month where nobody talked for like ten whole minutes. Then Sarah from accounting dropped her phone and it made that loud clatter on the floor. Everyone jumped, then laughed, and suddenly we were all complaining about the bad coffee. It wasn't about the phone drop itself, it was the shared surprise that finally got people to stop trying so hard.