Circling back to this thread after finding time to watch the whole video. Sad that it's DOA. They're trying to tackle THE major problem in open world type game design. The world is almost never meaningfully alive, and thus emergent gameplay doesn't really emerge. That's one of the major reasons BR took off, put 100 real players into a huge map and pit them against each other, and all sorts of emergent hijinks ensue.
I've kind of checked out on GTA, so I haven't really played through V or RDR2 yet, so I'm sure the illusion is a bit better than the older ones... but that feel when you spin your camera in a circle and all the vehicles you had just been looking at disappear and are replaced with other randomly generated cars, that aren't driving anywhere in particular, and if you do force the game to continue rendering them for more than 15 seconds they'll probably crash into something for no reason or otherwise do something that breaks the immersion.