Whether something is an opinion and whether it uses subjective language or not doesn't mean it's not a point worth discussing. You'd be ignoring the entire con

Whether something is an opinion and whether it uses subjective language or not doesn't mean it's not a point worth discussing. You'd be ignoring the entire concept of "inductive arguments" if you honestly thought that's the case. Arguments that aren't directly based on fact can still hold up if they're cogent. So I'd urge you not to give undue importance to the subjectivity or opinionated nature of an argument. (I neither agree nor disagree with any of your other points. Just that one particular thing.)