If an advertising channel then shows ads that breach license they are liable. A fairly simple licensing process will come into play and we can find new ways to fund things
Edit: Yes i do get a lot of the issues around regulation of tech - it's almost like saying regulation of every day life which is really broad. And the different bodies and approaches will also need to be broad. But i am a believer in markets and individual decision making and i also believe that personal information has in the past few years become a genuine new ... commodity? And we need to raise that commodity into visibility - to be able to put prices on it openly. Maybe it won't work, maybe privacy is like a human right and can only be dealt with at that level - but i don't think so - privacy to me seems ephemeral and usually poorly defined. Longer discussion to be had