Still, though, "Trump is a good president" remains an opinion. An objectively bad opinion, but an opinion nonetheless.
It's funny, as law dogs, we encounter "questions of fact" and "questions of law," which correspond mostly to "facts" and "opinions." This is an important question to law dogs, because as a general rule, courts of appeal can reverse or undo questions of law, but can't touch questions of fact.
Something quite similar comes into play in defamation law, where statements of opinion by and large can't be defamatory, while statements of false or incorrect fact can be.
At first blush, what is fact and what is law, or, similarly, fact and opinion, seems quite straightforward. But law dogs soon learn it is not. One legal talent is the ability to recast matters factual into matters of opinion or law, and vice-versa.
None of this really matters when it comes to the Trump cult, who are wrong on actual facts most of the time, as well as holding objectively and subjectively horrible opinions. Just pointing out the rhetorical trap that fact vs. opinion holds for most.