"Negative Nancy" is a phrase used to describe someone who is constantly pessimistic or always focuses on the negative aspects of things. Full definition
Lots of negative Nancies on N4G wont admit it but f PS4 had these features regarding games having local co op eveyone would circle jerk about how X1 does nt have it. (n4g.com)
It always feels different to the people who want it to be different i.e. Doomsdayers, people with political bias, the general negative nancy. (theirrelevantinvestor.com)