I agree, and of course there's an implied statement of opinion in screeds like GP's, but they set up such a tenuous chain of causality that I just couldn't help myself.

I don't know, if you ask me when in the field of public policy, this approach is a bad idea. When I encounter someone making proposals who is stating opinion as fact, I assume the person doesn't know the difference so I discount their opinion fairly strongly, because a lot if not most people in my experience genuinely don't know the difference.

Yes, journalism is a bit different, but typically opinion pieces either have OPINION written at the top of the article on the web, or appear in the opinion section of the paper. I generally stay away from opinion pieces because they deliberately try to convince me to a particular side of an argument, which usually excludes alternative information. I'd rather come up with my own conclusions.