Complete mastery of one’s native language in the spoken or written form has little relationship to one’s ability as a writer. If nothing else the minor grammatical errors and typos and other mistakes will carve out a distinctive voice for the writer and also let the reader know that what they are reading was not made by generative AI but rather made from scratch by a human being. Beyond a certain point past which the writing is clear, comprehensible, and pleasant for the reader – striving for an arbitrary standard of linguistic perfection is a distraction from actually having something worthwhile to say. Why should we say “this peice of writing is a rough draft, unfinished, not good enough for the eyes and minds of other people” before it has been scratched up with a red pen?
In other words turn in the gods damned paper it is likely good enough already