I dont think that this is really true, I strongly suspect that most people I know would consider someone drawing porn of them without consent a majorly icky thing to do, and would probably consider someone doing that to someone else to be a creep for doing so. The reason such drawings are less an issue is at least partly that the barrier to entry is lower with AI, since it takes a certain amount of skill and time investment to draw something like that such as to be clearly recognizable as any specific real person.

I mean, it did bother people, it just took more skill and time at using photo manipulation software to make it look convincing such that it was rare for someone to both have the expertise and be willing to put in the time, so it didnt come up often enough to be a point of discussion. The AI just makes it quick and easy enough to become more common.