A writer’s job is to ask if something is possible and then argue, through their stories, that it can or can’t be done.
A reader’s perogative is to enjoy it, whether it is possible or not. If they like it enough, they’ll hold the idea in their mind and explore it for meaning and possibility themselves.
And then some day, some scientist or tech wizard or mathematical minded reader will test and prove the theory that otherwise existed only in a story.
Can these theories be thought up by other people and not just writers? Of course!
But a story, when done right, lodges the idea in the imagination to percolate longer and give rise to new ideas over time. It starts the idea on the creative side of the brain. And who knows what that does to the scope of the ideas.
Tl;dr – STEM is important, we need people to believe in science again. And the Arts are important because we need people to WANT to believe in science again. They are all equally vital to society and human development.