@kellyromanych @xris @ClimateJenny @futurebird @r343l @alexwild note that if you have your contributions set to a Creative Commons license that doesn't prohibit derivatives and commercial use, you've already granted them (and everyone else) irrevocable permission to do pretty much whatever they want with them.
You can change the license field, but that doesn't have any legal effect on anyone who accessed your contributions under the original license. The best you can do is change the license for new contributions (if any) going forward and hope that courts decide that AI stuff doesn't get a total exemption from copyright laws.