I think you're misunderstanding my point. If you can crank out a custom app this quickly, you don't make a commercial app and then try to sell it on an app store. Customers pay you to make apps for their specific usecase. One app, one customer. And if a week later they want some new features, they pay you (or another freelancer) to add it.

Put another way, we programmers have the luxury of being able to write custom scripts and apps for ourselves. Now that these things are getting way cheaper to build, there should be a growing market that makes them available to more people.

Why do they pay you though, why not just do it themselves? With improving models and surrounding tooling the barrier to creating apps is lowered, and it's easier for a user just to create their own app, no 3rd party person needed.