If you had a contributor that plagiarized at a 2-10%, would you really go "eh it has to have a degree of novelty to be a problem" rather than just ban them? The different standards baffle me sometimes. You can find various rates mentioned here: https://dl.acm.org/doi/10.1145/3543507.3583199 and here: https://www.theatlantic.com/technology/2026/01/ai-memorization-research/685552/