Elon Musk – Optimus robot 'will be worth more than the car business'
cnbc.com
cnbc.com
However, I've worked with robots starting a research group at Joe Engelberger's Unimation in 1976 (https://www.google.com/search?channel=fs&client=ubuntu&q=joe...).
One of my recent efforts at CMU involved human/robot collaboration to change a car tire. I am currently doing research on self-reproducing systems, essentially robots building robots.
If Musk thinks he underestimated how hard self-driving was then I think he is seriously underestimating general purpose robotics.
That said, I really hope he succeeds. I want to be the first one to shake the robots hand.