Maxperson
Morkus from Orkus
NPCs are a little like traps. They really should involve some telegraphing and foreshadowing, and they kinda suck when they're essentially a black box. Motivations and objections are key to social interaction, and I personally don't see the value in making the players constantly play 20 questions to figure them out.
Yes. Puzzles have foreshadowing and hints. Even when the hints are recognized and acted upon that doesn’t stop it from being a puzzle.
For me it depends. To me a puzzle is something to be figured out and the words "Mad Tyrant" alone are more than enough to tell you that you probably shouldn't be insulting this person. There's nothing to figure out. It's told to you by the name alone. I just can't remember in this thread if it came up that the PCs were informed of this or not.
Now, if instead of being known as the Mad Tyrant he's just the Burgermeister and you have to pick up on his insanity and tyrannical methods via clues in his behavior and the behaviors of those around him, then sure, that would be a puzzle.