I was going to say, the main reason todo apps fail is because they are specifically about doing what people don't want to do.
If there were a generic way to unfuck your life on the other side of it, I could see it being wildly popular. Like a linear progression in weights, or a fasting diet, or a spaced repetition scheme, but for unwinding the effects of avoidant behaviours, with progress and results, that would be valuable.