Sure, lots of clever ideas appear first in science fiction, and lots of people in STEM careers read science fiction. But it seems to me that this is fundamentally the argument, "If you can't beat them, join them", and we desperately need to beat them.
That is, the imperative to reduce everything to a narrow question of how to increase profit margins is destroying us and our world. And it's become a trope for liberal journalists to criticize some trend or widespread business practice and throw in the "plot twist" that hey, guess what, if we made this change, we'd actually increase profitability! Living well is a means to improving productivity!
Well, fuck profitability.
And really, the humanities, and the liberal arts, are where people should be learning how to say that there are things that matter more than profitability. Truth, beauty, and love come to mind. In fact, I'd suggest that the real reason that the humanities and the social sciences are under attack is because they explicitly encourage social criticism and the positing of alternatives.
Setting that last point aside for a moment, if somehow we were to win an argument that the humanities deserved funding because that would support the writing of science fiction, and science fiction is a source of wealth-generating ideas, wouldn't that put the humanities in the position of depending upon patronage that is contingent upon the production of marketable ideas? Do we want to see book reviews that focus on whether the novel described marketable new products?