I think this shows the flaws in doing agentic designed apps. This is a really specific market that would be hard to make money from. Many people aren't going to think of using diary, most will use generic tracking app or even just notebook. Those that do won't spend money on it.

Another is that they don't have enthusiasm for the idea. Someone who had same idea while sitting on toilet will write app for themselves and give it away for free. They will have connection with IBS groups for promotion. They won't give up after weeks.