In fairness, 'opinion' is a horrendously vague and ill-defined word. It does double duty as (i) 'normative value' and (ii) 'personal understanding of the descriptive facts', which two senses are constantly confused - for example right here.

That's why we constantly get "it's just my opinion" used in reference to type-ii opinions (personal understanding of descriptive fact), when it's only really appropriate to type-i opinions (normative value).

Many conversations would be far clearer if it were abandoned in favour of more precise language, IMPUOTDF.