On international flights, there is a presumed dark/quiet time. During this time it is definitely considered proper etiquette to stay quiet and keep your window shade down. Yes, you are entitled to talk quietly and use your reading light, but minimize disturbances. Flight attendants should adhere to this and often times they are out of line. I'm with OP on this. The solution, IMO, comes down to retraining and some level of self-policing within the crews.