This'll probably sound nuts, but apart from the stupidity in that youtube video, which will definitely happen... one of the interesting things for me is if Hollywood would embrace that idea and "tweak" actors performances in editing beyond edits and into actual performance nuance... ie adjust their facial expressions, add words, movements, etc. It's just an interesting thought to me as to what a "performance" entails, and if the performer is open to such tweaking, and if the performer does it or the director directs someone else to do it - ala Andy Serkis.
Then we get into awards - if someone's performance is minutely tweaked after the fact, do they deserve a Best Actor award?
I remember back in the day people used to talk about 3d rendering dead actors like Audrey Hepburn - imagine if they get a model of her so precise and then Andy Serkis acted, minutely tweaked, using that voice rendering based off her past performances to put whatever words they wanted out there... they'd release one movie as a "gimmick" - but then if that's successful, economics of scale - they'd probably release more...
It'd be interesting if we even need actors in the future
Just another industry we can do without
Ah well, I'm just being pessimistic, as I am