That's not at all incongruous. If I'm saying "You are complaining about something stupid", I am not necessarily criticizing the concept of complaining itself, which would be hypocritical.

I seriously hate this argument. "You are nit-picking", "and here you are nitpicking my nitpicking, interesting that we are on exactly equal ground now". It's a dumb turn-around that could be used to attempt to silence any criticism of any criticism.

Sometimes, a criticism or complaint is not valid or frivolous. Pointing that out is not inherently invalid or frivolous.