Note: I am the author of this article.

The Apple developer fee has little effect on malicious submissions, what it effectively does is preventing free (open source) software. You aren’t significantly safer, you are merely paying for software that would otherwise be available for free. Note that Google also has a developer fee for the Chrome Web Store, far more moderate however.

What helps is consistent human review, like Mozilla used to have it. But Google established that automated review should be enough, so there you are.