It's like saying basketball is inefficient, when I pass the ball to a team mate I can loose it, better if I run the whole field on my own.
Programming is mostly a team sport as well, involving backend and frontend engineers, qa, design, product owners.
I mean, I would say basketball is inefficient: having one person run the ball or maybe two reliable players pass it across the whole court definitely seems most efficient.
The only twist in basketball is that there's another team trying to stop you from achieving your goal (which would also add to the appeal of mob programming greatly!)