Coordinated campaigns of hate through the mass media - like kicking up war fever before any major war you care to name - is far more concerning and has already been with us for about a century. Look at WWII and what Hitler was doing with it for a clearest example; propaganda was the name of the game. The techniques haven't gone anywhere.
If anything, making it cheap enough that people have to dismiss video footage might soften the impact. It is interesting how the internet is making it much harder for the mass media to peddle unchallenged lies or slanted perspectives. This tech might counter-intuitively make it harder again.
I have no doubt trust levels will adjust, eventually. The challenge is that takes a non-trivial amount of time.
It's still an issue with traditional mass media. See basically any political environment where the Murdoch media empire is active. The long tail of (I hate myself for this terminology, but hey, it's HN) 'legacy humans' still vote and have a very real affect on society.
If anything, making it cheap enough that people have to dismiss video footage might soften the impact. It is interesting how the internet is making it much harder for the mass media to peddle unchallenged lies or slanted perspectives. This tech might counter-intuitively make it harder again.