Two interviewers openly disagreed about my answer while I was still sitting there

System design round, I'd proposed a queue-based approach for something that honestly could've gone a few reasonable ways. One interviewer nodded along the whole time. The other jumped in with "I'd actually push back on that" and they went back and forth for maybe ninety seconds like I wasn't in the room.

I sat there not sure if I should referee, defend myself, or just wait it out. Ended up asking which constraint they'd want me to optimize for and let them answer that first, then responded to the sharper version of the question.

No idea if that was the right instinct or if I just got lucky that it gave me something concrete to hold onto. Made it to the next round either way.