This does show how perhaps the 'op-ed' doesn't quite work in its current form on this new-fangled internet thing.

I've talked to more than one person who assumed something written on the main domain was a 'proper' article, when in actuality it turned out to be an op-ed, blog (some new site did/does this) by essentially a random person, or something like that.

Maybe people made this mistake before and I'm only noticing it now?

I feel like this is only an issue with people who only skim the title and fail to actually read the article. The page itself makes it very clear that it's an opinion article, and if you're drawing conclusions from the url or title itself it's the fault of the person.