If no developer complained about anything nothing would change and the project would be slippery slope to oblivion.
Usually any project needs some kind of feedback loop to correct any problems and most of the time an important link in the loop is developers complaining.
It just needs to be done in a productive way. For example, retrospective is an attempt to direct complaining to be productive element in the process.
Also, it is a good starting point to be very cautious abut any radical opinions like that.
