I'm happy for people to try to make a business of this if the tools are helpful.
I've had a successful career, so I obviously had to develop my own strategies for managing it. But I'd be very happy if my kids didn't have to spend 20 years figuring it out for themselves. Monetize away.
Perhaps ironically, the less the app claims to do, the more likely I am to be interested.
I've only signed up for a paid mental health app subscription once -- and that was an app designed by a well-known psychologist with both an M.D. and a Ph.D., and even then only after reading his book.
Ryder Carroll is a good example. He created the bullet journal through trial and error to manage his own ADHD. He shared it for free. While he did write a book and partnered with a company to design a notebook (due to popular demand), he still gives away everything someone needs for free, and will be the first one to tell people you don’t need a special notebook.