A hypothetical guy works at a hypothetical startup that publishes a lot of blog posts, and he's not the greatest writer, so he uses a hypothetical service that does AI-based editing for him. He loves the service and recommends it to everyone. The startup folds and he goes to work at a different company and that company has a professional copy editor on the payroll so he doesn't need to use the service anymore.

He's churned, but he hasn't rejected the service. He just doesn't need it anymore because his circumstances have changed. If he needs the service it offered, he could presumably re-subscribe to it later.

My personal take is that it's more of a service (ie Software-as-a-Service). So, you use the service for what you need then stop when you don't need it anymore. That's not rejection that's not needing that service anymore. Say for example, that I have car insurance. I sell my car and cancel the insurance. Does that mean I'm rejecting the insurance company. No, I just don't need that service anymore.

As this stuff scales you need for think of churn as a cohort and start looking at why. I don't argue that. But, framing it as rejection is incorrect. Guess it depends on the service you're providing though. If it's something highly personal where you, the person are highly involved, then it might be rejection. But, I think that's pretty niche.