Hmmm... I sort-of understand what you're saying here, but I absolutely do not believe in consciously inserting a message/agenda into a story, as I think such stories end up being preachy. I talk about this here.

As you say, you might see a message (or others might) after the fact, but the most important thing to bear in mind is a good story well told, which involves a character arc in the protagonist (or supporting characters affected by the protragonist), and how and why they change is what is most important. That is what will resonate with readers/viewers.

I suppose what I'm saying is that all films/books/Tv programmes do have a message or moral or whatever, but I don't think it is necessarily a good idea to consciously insert one. I think with a good storyteller, what is important to them will be inherent in the narrative if they simply tell a good story with no conscious agenda.