It is your prerogative to tune your servers as you see fit, but as LLM adoption increases you'll merely find that your site has fewer and fewer visits overall, so your content will only be utilized by you and a vanishingly small group of other persons. Perhaps you're OK with that, and that's also fine for the rest of us.
It's strange you mention theft, and then say it isn't about money. For me, and many others, it's about practicality and efficiency. We went from having to visit physical libraries to using search engines, and now we're entering the era of increasingly intelligent content fetch+preprocess tools.