It came from economists asserting the difference between modeling human behavior vs. the behavior of physical objects. In that sense it is not meaningless. It's an important distinction that in order to model human behavior, we have to accept that people's goals are myriad and constantly shifting, and that we can only come to know their goals or preferences by them being revealed in action.
Is it really that different? Try to attach an object to several springs and see if it behaves "rationally".
Physical objects do not have free will. They don't act towards goals. They conform to unchanging mathematical patterns.
Humans do not. What I do today cannot be accurately used to determine what I will do tomorrow.
The debate takes on a different dimension when you're talking about political policy, when the weatherman passes a law forcing everyone to wear raincoats on days of high chances of precipitation.