If I say something is "best" or "good" or "total crap", those are value-judgements, and value-judgements always carry a provisional in-built "in my opinion". In the same way, any statements about fact carries an inbuilt - "I believe this to be true."

No harm in bringing them out sometimes, but it's really just a way of making the sentences balance better. Like when someone says: "All I can say is..." and so on and so forth. A rhetorical flourish, and long may rhetoric flourish.

Freedom of speech can mean two things - one is "noone has the right to stop me saying what I choose to say", which broadly I'd agree with; or it can mean "When I say what I choose to say, no matter what it does to other people, that's my right and nobody else's business" - and that I think is far from true.