I see your point.

Given their goal is to show that we have reasons to be more optimistic about the world, I think the quiz setup makes sense. It highlights that we can't even distinguish between optimistic 10% and pessimistic 50% for issues we regularly hear about in the news. I'm exaggerating here, but the 50% would have been obviously wrong but isn't because we didn't look at the data at all, instead made an assumption based on our perceptions. This hard hit is a good thing and fulfills the goal of the quiz.

But yes, choices of [1%, 10%, 20%] would likely make more people choose 10% than among [10%, 30%, 50%] when 10% is the right answer. Thanks for the insight.