unclear if this hand is fitted to the androids they had walking around at the event. I wish I didn't have to be skeptical at how much of the Optimus presentation is CGI but I guess having a product that's hard for people to believe is real is a good problem to have.
The robots walking around were Gen 2, this hand is for Gen 3
Disney Imagineering had that over a decade ago...You can see the robots designed for heavy constant use in action at the Rise of The Resistance (DL, DW), Tiana's Bayou (DW), Guardians of the Galaxy ride (CA, in the queue).
Not exactly. If you actually look at those hands on Disney's A1000 animatronics, they are actually pretty basic, usually 5 to 6 degrees of freedom at most. They are designed to be simple, because as you mentioned they are in use for like 16 hours a day. The more complicated you make it, the more likely it is to break down. Each hand is designed to give the illusion of life with the least amount of moving parts possible.
Here are some pictures of the A1000's hand: https://imgur.com/a/kmh3fLX
A more accurate comparison would be the Shadow Robot dexterous hand used by openai to rotate a block one handed about 6 years ago. That one actually has 2 more DOF than the new tesla one. Like tesla's, it's also cable driven, but it's pretty slow and jerky.
What I think the new tesla bot hand now achieves is the lifelike A1000 movement with a vastly more dexterous range of motion like the Shadow. It's kind of the best of both worlds.