Good find! Agree with pretty much everything mentioned in the video. I remember when I first played through JWE the first few of islands were great fun and tended to offer plenty of new things to do, but then that's where the fun seemed to plateau a little until more updates & DLCs came out, but even then there wasn't too much in the way of extra gameplay mechanics being added. Hopefully the sequel will have much more depth, especially in the later levels.
Of course, the dinosaur personalities thing is what I'd say is most important for truly bringing the game to life the whole way through and on top of that if more advanced behaviours allow for better interactions with either the park workers and/or guests then Frontier would be starting to hit the nail on the head. I think just by adding more dynamic interactions, this would open up so many more possibilities with management of the parks.
E.g. dino waste management could be a thing, as could enabling juvenile dinos to develop into adults & breed, as well as additional mechanisms for keeping workers safe while feeding the dinos, nursing/medicating them and maintaining their enclosures and the attractions around them.