Browsers are getting built-in LLMs for doing things like summarization now, such as https://developer.chrome.com/docs/ai/summarizer-api - so even if you could license your creations in such a way, it wouldn't prevent a browser extension or someone using the JavaScript console doing it locally without detection. To me, the idea feels arguably similar to asking to opt out of one's words being able to go into a screen reader, a text to speech model, or certain types of displays.