Do you agree with this viewpoint?:
Speaking only in absolutes is undeniably the best way to communicate.

But to be serious, there's a benefit to having people express themselves in a way that reflects the confidence they have in their views. You might point out that true certainty is impossible, but this is precisely why I don't think that we should preface every opinion we have with "in my opinion". Of course it's my opinion, that's why I said it.

Myself, when I see someone always talking in absolutes on a topic - I'm skeptical wether their level of certainty would even allow for a honest debate or discussion.