Surely deepfakes will be just different enough to the subject to create reasonable doubt that it depicts the subject.

That’s a major assumption. Do people really think a school board will really consider that when a student creates a fake Only Fans of a teacher? A random University or Company doesn’t even give reason for denying an application when they see any form of online nudity? People are lazy as fuck and will just move on to the next candidate or let someone go to save their own image rather than that off the victim.