My totally unscientific hypothesis is: "solving problems you do care about" is usually the easiest way to make money, e.g CRUD and web API. Once your skill is

My totally unscientific hypothesis is: "solving problems you do care about" is usually the easiest way to make money, e.g CRUD and web API. Once your skill is more polished and your experience is wider, then try to look for jobs where their goals aligns with your interests.