I know the point you're making because we struggle with something similar in a different industry. I think we've already seen the "phase out" of small developers in the App Store; rarely if ever does an indie company make it into the top 25 charts or, more importantly, the Spotlight app section. I don't really anticipate it becoming much worse than this because the submission process is mostly effective at weeding out the fart apps and broken software that often makes it into something like the Android store, and apps at the bottom are naturally hidden from the end user anyway.
I think the reason Apple can continue to allow mediocrity into the store is because those apps don't actually reach many end users and they pad those 700k apps and 25 mil songs vanity metrics. This is opposite someone like Groupon or a high end designer brand, where exclusivity is a major factor and driver. The only parts of the App store where exclusivity is a factor are the top lists and the spotlight section, which as I mentioned above have largely excluded small developers for a long time.
I think the reason Apple can continue to allow mediocrity into the store is because those apps don't actually reach many end users and they pad those 700k apps and 25 mil songs vanity metrics. This is opposite someone like Groupon or a high end designer brand, where exclusivity is a major factor and driver. The only parts of the App store where exclusivity is a factor are the top lists and the spotlight section, which as I mentioned above have largely excluded small developers for a long time.