I can't say I know much about licensing and/or GDPR stuff, all I know is that if it's public, I don't have to agree to anything and I can do whatever I want, which is great for me and my business. From the other side, yes it sucks that people can take my stuff and profit from me and there is nothing I can do about it and no way to enforce it and I probably don't even know it's happening. (sounds like ad tracking!)
The way things work in North America at least to my understanding is that it doesn't matter what license you use, I don't have to agree to it to scrape it and use it if there is no click wrapper. I guess if you caught me explicitly using it in a certain way, I could get in trouble, but that is not easy. What you propose sounds reasonable, but I don't know how it would be enforced or if it would still stop people. I'm owed 30k in consulting wages and I can't even make it worth my while to pursue that from a legal standpoint, let alone try and sue some unknown and/or potentially massive company or scattered random ghosts across the interwebs.
