Phone sex does make money, but it's a very niche industry. Most people think they can just 'talk dirty' and make good money. But the reality is you have to dive into some crazy fetishes and be willing to explore all kinds of role-playing scenarios.
For example we have a list of categories that performers can select:
https://sincats.com/category-models.html
It also takes time to build your clientele. But once you do you'll have regular callers that will keep calling you for years. If I can be of any help hit me up.