To remain a functional society, we'll have to trust centralized news outlets more than social media sources, or have computer programs which validate images/videos based on either metadata or statistical noise. Maybe even a suite of these programs and several centralized news outlets verifying. Or maybe some form of content delivery that encrypts legitimate videos at the time of recording so that when we recieve a video encrypted in this way, we know it's unaltered? I'm tired so i haven't thought this through.

Anyway, when video synthesis is perfected, we will need to treat video and images exactly like we do text now. Goodbye to the days of automatically trusting all video as authentic unfortunately. :(