Even as AI generates more writing and code, we still have a way of ranking quality: Good writing and successful projects tend to get more popular and prominent. This selection can allow LLMs to continue to improve. They get a huge flow of slop, but they generate based on the patterns correlated with better quality. The model developers can also develop better ways to curate the input data themselves and keep the slop at bay. It's not a guaranteed or trivial mechanism, but I don't think we need a new breakthrough either.