A huge difference between bespoke generated AI apps and one click download apps is that the friction drops dramatically.
Downloading the app may be one click...but then create an account. Attach a CC. Follow a tutorial. Figure out the app even more.
With LLM apps, there is none of that. You created the app so you pretty much know a priori how to use it. If you are unsure the model knows and you can just ask. If you want it to do something different, the model can just change it for you.
The modern software paradigm is building software that covers as massive of a solution space as possible, so as many users as possible have a problem that is covered by that space. You end up having to make lots of compromises and unintuitive steps to cover all the bases.
LLM apps cover your problem space pretty much perfectly, without anything more.