A practical step is cartoonists should register their name/signature as a trademark. Arguably they should have been doing this before AI came along, but definitely they should do it now. Registration makes enforcement easier.
Unfortunately, in the US these laws have barely any teeth in the first place, and even if they did, well you are probably familiar with the corruption things and malfunctioning justice system stuff they have going on there, as you hear people often speaking, very matter-of-fact that in a court situation, the party with more money simply wins.
(not really surprising that people are going Butlerian Jihad against data center construction, is it now?)