If any of those 16 developers were at the by some allegedly 20x productivity with AI models it would have been positive on average, but none were even close to that.

So I feel its fairly safe to say that models aren't even close to 10x productivity gain for average developers, so developer jobs are not really in jeopardy so far. If it was easy to be more productive with AI models then this study would have found that, the only productivity gain this study could have missed would be if it was really hard or if the gain was really small, and both of those means it wont replace most developers.

They tested on 250 tasks, ultimately the number of developers doesn't matter that much here.