I think that you are missing what unique condition of recent past has changed with deepfakes. In medieval times there was two levels of evidence: you could see something with your own eyes or someone could tell you about something. Book saying there are people with brown skin in Africa was no different in evidential power than book saying there are people with dog heads, you were left with your priors. When photo and video was invented, we got new level of evidence, not as good as seeing something personally, but better than anything else. With deepfakes we are returning into medieval situation where “I’ve seen source about event X” has very little difference from “someone told me about event X”.
I think that you are missing what unique condition of recent past has changed with deepfakes. In medieval times there was two levels of evidence: you could see something with your own eyes or someone could tell you about something. Book saying there are people with brown skin in Africa was no different in evidential power than book saying there are people with dog heads, you were left with your priors. When photo and video was invented, we got new level of evidence, not as good as seeing something personally, but better than anything else. With deepfakes we are returning into medieval situation where “I’ve seen source about event X” has very little difference from “someone told me about event X”.