I'd heard this advice plenty so felt ready to deploy it when I had a toddler.
I have a toddler now, and have tried this approach a number of times. She just says "no" to the choices....
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.
When my son was little, he would say things like “Yes means no and no means yes.” He would also say things like “milk is good, butter is made from milk, cake is made from butter, why can’t I have cake for breakfast?”
Through persistence and speaking to him calmly, he eventually stopped his petulance. Usually if he wanted something, we would only give in after repeated conversations. We wanted to explore decision making with him and ensure he would not quickly want something else. The main thing I wanted was for him to talk and explain why he wanted something so bad.
I believe he only threw a full tantrum a handful of times. When that happened we followed the advice of pretending to leave without him. When he realized we were not rewarding his tantrum, he stopped.
In short, we wanted to reward him for communicating not for throwing a tantrum.
Yep, it works for majority of children, but not for all of them. Folks that had a couple of kids with whom it did work spread it as a gospel.
You can try many other things, and maybe you’ll find something that works some of the time.
“What do you want?” can be “NOTHING!”, can be something. “You want this, but the reality is this and that. How can we deal with that?”
If kid is upset it usually helps to validate their feelings first.
Also, my kids are not yours, so take this with the grain of salt as well.