Their lawyer, if your depiction is covered by personality rights and the situation is significant enough to pursue damages. This is pretty much never going to be the case with an individual drawing (especially if only available non-commercially), but there are plenty of examples of people winning or settling for substantial sums after, for example, their likeness was used to advertise something without their consent.

> So why are we trying to stop AI?

Because a bunch of companies are trying to launder various legal liabilities (copyright, personality rights, etc) through the claim of 'it was just training data'.