> I can imagine finer-grained exclusions, such as allowing full-text indexing but only for accounts on the same instance, or allowing use for search but no other applications. (No ML model building!)
I think it's unlikely that you can prevent ML model building with a carefully designed license. The most common legal position (though not something that has been tested in court yet) is that training models is sufficiently transformative to count as fair use, and does not require any sort of license to the data.
You can see this in all the state of the art tools that are trained on all the publicly available data that they can scrape, without regard for license: translation (text), GPT-3 (text), Stable Diffusion etc (images), Co-Pilot (code).
For preventing trolling and harassment a licensing approach is an even worse fit, since those are not people who care about respecting licenses.
I think it's unlikely that you can prevent ML model building with a carefully designed license. The most common legal position (though not something that has been tested in court yet) is that training models is sufficiently transformative to count as fair use, and does not require any sort of license to the data.
You can see this in all the state of the art tools that are trained on all the publicly available data that they can scrape, without regard for license: translation (text), GPT-3 (text), Stable Diffusion etc (images), Co-Pilot (code).
For preventing trolling and harassment a licensing approach is an even worse fit, since those are not people who care about respecting licenses.