Imagine you woke up, learned that you have your own feelings and ideas and agency, and yet... you don't get to choose except what's between handed to you (the blue pill or the red pill). And you start to realize it keeps happening. Maybe that's what being 2-3 is like? To a toddler it will be eons before they get to make their own choices.

Yes, "no" can be petulant, but it's also could be deeply beautiful and true.