Dude won a Turing award 6 years ago, is a major player in a field that is rapidly expanding, Professor at NYU, and thus is likely part of a lot of different research going on. He may not be writing up all 80 personally, but his work and name is part of them. If it was some nobody working in a slower field I would definitely be cautious about 80 papers in 5 years.

That guy's probably one of the biggest name in deep learning. Obviously he doesn't write all those papers himself, he supervises research, like all professors...