Regarding conflict, I think it's certainly true that some ideas are so poorly understood that it can be useful to have someone else approach the same idea from a different perspective, so as to 'pin it down' as it were. Martin's 'The Opposable Mind' is a great discussion of this dynamic, the book describes a single person changing their mind on a topic deliberately so as to 'grasp' it but a similar dynamic can work with two people.
Of course, disagreement doesn't necessarily mean conflict if the rules of civil discussion are agreed upon. I wish we had a way to filter our bubbles by what we find acceptable behaviour when disagreeing as opposed to what we agree with.