You act as if Netflix, or a grocery store, have no control of what they put on their platform/shelves. They decide what they sell. And this would be more like a grocery store selling smaller dildos aimed and marketed at preteens. That wouldn't go over well in any area.
I have a feeling South Park would mock the movie and its makers, not the outrage surrounding it. They seem very opposed to the sexualization of kids. Mocking it with Raisins, a store like Hooters, but with young girls. Also, an episode mocking beauty pageants, with a judge jerking off to the young girls.
Of course they have control over what products are available on their platform. But just because you don't like the product doesn't mean they won't make it available for others who do.
I reject your false analogy. It would be like making thongs for preteens and having them available. Oh wait, they do have that...
I will add that simply because you find something to be sexual doesn't mean that it is sexual intrinsically.