I don't get this kind of logic. "If you don't like something, divert your career path and become an expert in said field, and make it better."
Why don't we just shut down the whole forum then, or never discuss anything besides ponies shooting rainbows out of their asses?
Progress is made incrementally, built on previous successes and influence. We didn't go straight from lightbulbs to microprocessors. AI behaviors aren't any different. We don't have to jump from F.E.A.R. to Hollywood to make progress.
The point isn't "challenge." You can create an AI character that can respond to the player lock-step and shoot him between the eyes every time. The point is to create a SINGLE-PLAYER environment with interesting and balanced AI behavior. The requires creating A LOT of behaviors.
I just gave an example earlier of a developer who expanded on the behavior set with one game, and then the next game abandoned those behaviors. THAT is what I find puzzling.
Why not move forward? Keep building the behavior tree and branching out to more varied, interesting behaviors? There is no reason not to, other than resources. It takes a lot of time to build and debug, and if gamers don't seem to be interested in improvement, then they're not going to see the value.
I'm always happy to see AI discussion, and see no reason to throw out the "don't complain, play MP" card in an effort to halt the conversation.