We already have versions of these robots. I don't think it's as wildly unsolved as you make it out to be. A few key efficiencies gained in any part of the process could tip the scales. I would bet something decent is on the market within 10 years.
If it's not C3PO it's a Boston Dynamics dog with a couple appendages, better software, and automated manufacturing.
If it's not C3PO it's a Boston Dynamics dog with a couple appendages, better software, and automated manufacturing.