architecture – human computing at duolingo

Duolingo is given in the video TED of Luis von Ahn and in many articles, illustrating how he uses the human calculus to translate texts / articles, etc.

Is this still the case? Does Duolingo anno 2019 still use human calculus to do translations? If no, could you explain why this is no longer the case? Or do I post articles about it?

Basically, I would like to know why duolingo has stopped using human calculus. Was it because the quality of the translations was not good enough? Duolingo could there be scenarios in which human computing would still be useful?

Thanks in advance, Tim