Even in debates seeking truth, I think it's only an effective technique in a small subset. It doesn't work if the disagreement is because you're both just aware

Even in debates seeking truth, I think it's only an effective technique in a small subset. It doesn't work if the disagreement is because you're both just aware of a different set of facts. It doesn't work if the disagreement is because you have different fundamental goals. It doesn't work if the "debate" is actually a misunderstanding where you and someone else understand a term to mean different things. Amongst truth seeking debates, I feel like most casual ones end up falling into one of the above categories (more "academic" debates, the kind you find in philosophy classes, might be less likely too, because topics you can usefully debate are the ones actively discussed in those contexts). Also I'm not sure I agree that debates seeking truth are rare, they are just publicly broadcast less frequently so you come across more of them. Certainly I debate close friends and family matters on a fairly regular basis (for fun and learning).