Interestingly (ironically?) I've heard of some bloggers intentionally adding typos to their posts to ensure the post looks like it was written by a human and not AI.
That seems easy for AI to adapt to, and has a massive side effect of calling the author's reliability into question. Are those people going to go back and fix the intentional typos in a couple of years once AI spam is also full of typos?
Edit: "Unnecessary" might be my judgement, instead of "acceptable."