I think if people were purely using LLMs to convert their own writing into a publishable post, that would mostly be fine, but in practice people seem to be outsourcing the entire writing process ("Write me a post about X"). I predict that if someone actually had an LLM do an hour-long interview about some topic and then write a post about it, or wrote a post-length prompt and then had an LLM turn it into something publishable, the results would actually be fine (likely still running into LLMisms like going on tangents and focusing too much on style, but that's minor).

It would be interesting to try a policy of "you can submit an AI-written post as long as you attach either a Google Doc with an entirely-human-written prompt longer than the post, or a transcribed interview where the human portion is longer than the post".