[johnea]

I had the same question.

I thought reading the paper in Nature would give some more insight, but no.

I was looking for at least an estimate of what they thought world population should be, but that doesn't seem to be included in any of the text...

[oskarkk]

Because estimating the world population wasn't the point of the paper, and extrapolating their results for the whole world wouldn't be very good science. But discussing something that the paper authors didn't discuss makes a good clickbait title. Especially with the title here on HN, which presents the possibility as a certain fact.