Most people would prefer an excellent language learning app to simply be available and ready for them to use, rather than having to come up with how such an app could best work, and to get an AI to implement it by themselves, and having to iterate on that. Just like most people simply want to buy nice clothes, and don’t want to become fashion designers and managers of a clothing factory. So far it doesn’t look like AI is making the former (readily available excellent apps) more widespread.
As someone also building a language-learning app for myself, it's not too hard to create an excellent app right now, but the "readily available" part of your requirements is now 10x harder than a few years ago. Users are getting bombarded by new apps, so marketing an app, which was already hard before AI, is now much, much harder.
I could try to market this app, but I tried that 2 years ago, and it was already essentially a failure. So I'm probably going to keep it for myself or just try to find a few users who like it and will use it for free.
I think I agree. But it's nice to have the option. Furthermore, i think it's too early to see the results of this, as technology takes a while to diffuse. Since there are so many people trying to take advantage of the hype to make a quick buck, it takes time to figure out what is actually useful and what is not