This may not be what is meant here, but I wonder if in the future anybody who actually bothered to learn to write well will automatically be flagged as likely having used AI to write their prose.

For instance, everyone seems to believe that em dashes are something only an AI would use -- but I've been using them in my writing for a long time.

This doesn't read like an LLM at all...

I wonder if the more we use LLMs the more our written patterns will begin to match them. Those of us who work with them the most are likely to be affected earliest.