Once you start figuring out who your ideal reader is, someone always says "Yeah yeah, I get it" and then starts complaining that they're problem isn't the WHO it's the WHERE, as in "Where is my reader?"
They're all over the place, but you're going to have to consistently, intentionally, and regularly go outside your comfort zone or usual "marketing" habits to find them.
Things like a landing page. Or a promotional podcast. Or a newsletter. Or some graphics. Go just outside what you're used to and you'll find new readers.