> I think it can be OK if AI is used to polish up one’s message
Asking it to identify problems such as spelling, grammar, or general clarity is fine.
If you tell it to "polish" many commercial LLMs will absolutely slopify your text with characteristic AI catch phrases and non-sequiturs. Beware.
Indeed. And if someone then shares that output verbatim, they'll undermine their own credibility. They can guide the AI to tidy it up, or do it themselves. The issue is not in using AI for writing, but in not using it consciously.