Effectively, RTwP posits that every character in the game is stupid (no matter the character's statted Intelligence), and they remain so until they are touched by the inspiring hand of the gamer-god. After that brief moment of inspiration, though, the characters immediately go back to being stupid.
In turn-based, every character is only as stupid as the gamer chooses to make them, since all of a character's abilities are available to you at all times, during both unimportant rounds and critical ones, whether or not you are good at twitching. Which of the game types a person likes better is then generally based on how twitchy they are.
So, turn-based is purely about the gamer's mind. While RTwP is about the gamer's mind, his twitchability, and how much of the gameplay the developers choose to have handled by the AI (instead of having the gamer, you know, actually play it).
And so it will remain, since the RTwP AI can't be advanced too much more than it already is without the AI taking over the gameplay completely.