Because that idea is supposed to come from your brain not a self-writing Harry Potter pen - since that's what you're comparing AI to.

The question is though, why does this bother you? The internet is huge, you're welcome to spread your AI generated wisdom on 99.9(9) of the internet, so I don't see your problem.

Ahh, it doesn't pay you money. Well, you see, why would it? Why would anyone pay for AI generated content?