➡️ Content warnings on fiction are a courtesy.
➡️ Not every medium of fiction and storytelling has or is expected to have content warnings or extensive tagging.
➡️ Print novels do not traditionally warn for content in any way.
➡️ Until AO3 came along, fanfiction did not traditionally warn for content in any significant way.
➡️ An author is only obligated to warn for content to the degree mandated by the format they publish their fiction on.
➡️ Content warnings beyond the minimum are a courtesy, not an obligation.
➡️ 'Creator chose not to warn' is a valid tag that authors are allowed to use on AO3. It means there could be anything in there and you have accepted the risk. 'May contain peanuts!'
➡️ Writers are allowed to use 'Creator chose not to warn' for any reason, including to maintain surprise and avoid spoilers.
➡️ 'Creator chose not to warn' is not the same thing as 'no archive warnings apply'.
➡️ It is your responsibility to protect yourself and close a book, or hit the back button if you find something in fiction that you're reading that upsets you.
➡️ You are responsible for protecting yourself from fiction that causes you discomfort.