Here's the interpretation. Tom Cook has ideas. They aren't particularly interesting ones (they aren't 'idiotic', rather they seem mundane). Tom Cook made statements including his ideas. He is nobody's patsy.
WP made an appeal from authority in its article about Tom Cook. It implied that his ideas were interesting somehow because he is an authority figure. But on their own - no the ideas are not anything new.
I honestly don't know how a newspaper can make it more clear that something is the opinion of an individual person.
If this is an appeal from authority, then so is every op-ed written by every powerful or popular person ever.
So I would agree with this, sans the universal (there are powerful people who are experts in an area of law as a counterexample).
How could a media outlet make it more clear something is an opinion? They could put it in the title and in the body of the article as a start. They could add content to contextualize the opinion and remind the reader that the opinion maker holds no authority on the matter. They could link to opinion holders with opposing views but equal status. There are a myriad of ways they could do this - some of them very minimal ("Tom Cook opinion: Pro-discrimination 'religious freedom' laws are dangerous").