I'll be more descriptive: Applications (not games) developed and published for macOS and iOS by lone developers with little to no experience on those platforms

I'll be more descriptive: Applications (not games) developed and published for macOS and iOS by lone developers with little to no experience on those platforms is overwhelmingly unlikely to be used by enough people to reasonably justify its development. There are exceptions to this for specific niche use-cases. There are situations where this has not ended up being true. There are times where one might want to write such an application to scratch their own itches with no real need or desire to gain a critical mass of users. None of these invalidates my general point.