This just seems like a incremental step to me. Boston dynamics have been making biped robots for years. And it goes without saying that car manufacturers have been doing the same but much more specific bots to build certain parts of the vehicles.
The video is somewhat vague, and he didn’t seem to mention anything different than what Boston dynamics has already been doing unless the distinction is that a Tesla bot will be affordable to consumers (which boston dynamics has just started selling their bots to companies).