She runs one of the biggest newsletters on Substack. Probably earning a millon dollars a month from it. But that's pretty far off a billion. AI editors also aren't great - they help if you can't afford anything else, but as soon as you make enough to hire a real person you probably should do that.

I'm not much of a writer myself, but what little I do know about writing suggests that a "not very good" editor is actually much worse than none at all. That is, arguing with an LLM about my writing is probably going to make my writing worse, not better.