There is a difference between false praise and every thread looking like "What's this?! You dare call yourself a startup? You're attempting to solve a problem which other people have attempted to solve before, and your solution looks like something two guys could have made in three months! Why are you in YC and not me?!"

Ideally, we'd be aiming for constructive advice. "I would not use this" can be constructive advice, but it isn't most of the time I have heard it here.