Saw a couple of them being torn down on my street (Greenwich Ave). Although it seems like they're targeting sheds that are 'unused or have a history of violations', don't exactly know how they would gauge which sheds are unused and I can't imagine the restaurants will willingly part with the sheds either. Allegedly more than a 100 sheds have been taken down thus far.
Edit: My personal take after reading some of the comments is that even if they are replaced by parking spaces, at least parking spots won't cause further rat infestations and I can cross the street without being blind to bikers/scooters. The main negative for me is that this will probably mean the restaurants will encroach on even more sidewalk real-estate, which is already a rare commodity - especially in the village.
https://www.thrillist.com/news/new-york/nyc-tears-down-unused-outdoor-dining-sheds