What's up with generic disapproving diplomatic statements from other civs in Civilization 5?

Solution 1:

These sort of messages are typically received from civilizations that are hostile to your own. I believe the idea behind those is

  1. To let you know that civilization is hostile to you.
  2. To give you a hint about the areas in which you are lacking (e.g. if they say you are uncivilized, it indicates your culture output is too low).

I'm pretty sure that among the two response options, one is just to slightly increase the hostility and one to slightly decrease it, basically giving you some influence about the future of the relations.