Well, i have owned too much consoles and played most of them since the 2nd gen, and i always found a hater for that console:
NES: People with FAMICOMs hating the NES (I'm a FAMICOM owner but i didn't do that, but i've had friends that argued about the lockout problem and the games that received less features because of the PIN use on the NES games), so the NES hate was in-house...
Master System: "It doesn't have any games, all my friends have the NES"
SNES and MegaDrive had their fanboys fighting each other, today me and my friends play Brawl and discuss about Mario and Sonic fight back in the days...
N64: "What the f*** is with the cartridges"
Playstation: "3D is not the best", "loading times suck", etc.
Saturn: "You call this 3D???", "Where are my J-games", "Already working on another console?? This is CD and 32x all over again"...
Dreamcast: "Still CDs??? Sony will start with DVDs" "Already gone??? F*****"
PS2: "Emotion Engine is a fraud", "loading times again"
Gamecube: "1.5 GB is bulls**t", "That purple cube excuse for a console is for kids"
Xbox: "Is Microsoft, it's not reliable", "It's only a shooterbox", "it's too big"