This article by Jason Cross, writing in Macworld, is harsh but mostly fair. The last line of this paragraph, in particular, stood out to me:
It would be a trivially small amount of money for Apple to create an internal group dedicated to proactively finding and eliminating scam, copycat, infringing, exploitive apps. But every one it finds costs Apple money. And doing nothing isn’t hurting sales, not when it’s so much cheaper to just market the App Store as so secure and trustworthy. Apple seems to view App Store trust and quality as a marketing activity more than a real technical or service problem.
It is hard not to feel the same way after years of this same sort of complaint. Apple often says the App Store is trustworthy, and that every app is “held to the highest standards”. But it does not take much digging to find apps that fail to uphold those promises. For example, an App Store search for “who blocks me” finds apps that promise to reveal who views your social media profiles and who is blocking you. Neither of those capabilities are supported by the APIs of Facebook, Instagram, or Twitter. But there are dozens of apps that claim to offer that functionality, most of which require the purchase of an expensive subscription.