With the amount of power the copyright lobby has, who knows it might be true. However advertising is not the only industry where visual arts will be affected. Gaming, Comics, Animation, VR, Movies etc will be affected as well. And regulation isn't going to keep up across all the countries.

Even if we assume the above rule is made, there is no way to prove it because even if a human does it, he might still use the help of photoshop etc which are planning to integrate such tools currently. Most favorable outcome I see out of this is for famous/competent artists to license out their style of art to these generation companies which then train their models on them (which sounds win-win but won't be as profitable as it is today)