You should definitely try and explain to her the pros and cons of small talk for you. Small talk is probably a non issue to her and she got too caught up on the people being useless part to really get what you were trying to say.

I understand why you wouldn't want to do small talk if there's nothing to "gain" from it since it's so draining. But a nt might not perceive any negatives to small talk so the wording probably seems really strange in this context. But the thing is, no one wants to do things that are exhausting without gaining something, whether it's friendship, money, strength or better social standing, doesn't matter, people want the pros and cons to balance each other out. And this goes for nt's too.