I've been working on my project, a paid mobile app, for five months now.

I'm pretty confident I can release it in October, after some 500 hours of work.

Usually in these discussions I get "so it has zero users then".

One time someone on here told me that for AI to prove its worth for software engineering, my application would need to be in use already for at least ten years.

What value do you expect a 5 months of work app not launched yet to have? You might pretty much have wasted 500 hours if nobody want to pay for it.