How is the Anatta (not-self) doctrine useful?

My question today concerns Anatta's *usefulness*. What good does it bring us to realize that the "self" (*what* things are and *who* we are), because it is permanently changing, is therefore not real ? (that there's no "this is like that" or "I am like that" : only "this is", and "I am") ? Personally - if this is Anatta, if I didn't get it wrong, realizing this gives me a sense of freedom (as knowing that I am born and that I die at each moment makes me stop clinging to ideas I sometimes have about myself). Is this what Anatta's supposed to produce ? Not-clinging to reach Nibbana ? Thank you !