I would assume the questions are of the simple, "What facts did we state?" kind, rather than requiring some deeper understanding or inference. So why would you allow someone who couldn't grok the facts to comment? If my assumption is true then it works as a reasonable anti-bot measure, allowing wrong answers would negate that.

No

It would be funny if it still let you comment, but it showed your test results besides your comment.

Or how about shadow banning the user on that specific article? Make it appear their comment was posted, only on their logged in account (and maybe IP address). Rest of the world wouldn't see it.

Works very well, but the massive lack of transparency will make it difficult to justify and ultimately creating paranoia and scissors in the heads of people.

I would not want to participate on such a platform forcing me to double check if my contributions were actually published or simply hidden away for some secret reason.

It's these pieces of accountability that go a long way to have users compliant with moderation.

It would be funny if so many didn't already wear their ignorance as a badge of pride.

Imagine an article on vaccinations--many who would be posting exactly the sort of nonsense you'd be hoping to prevent would wear their "understood 0% of the facts in the article" as a badge of pride, and others who agreed with them would interpret it as such.

At least 0% would require more knowledge than guessing. You might even accidentally educate a few anti-vaxxers, who would be forced to learn what they were disagreeing with. (Yes, I know it still wouldn't help.)