My stance is that you cannot pretend the power dynamic does not exist. Boss can fire worker, worker cannot fire boss. Consquences of getting fired range from irritating to life-threatening, depending on worker's resources. Consequences of having to fire someone... not such a problem. You ignore that reality at your peril.

If the boss wants workers who can say "no", the boss has to create an environment where people don't have to fear the consequences of doing so.