I'm not sure I see how they get to profitability
Currently, they are a high variable/labor cost company, losing billions per year because they have to pay drivers and price below cost to gain market share and a customer base. Once their self-driving vehicles are perfected, there goes the labor cost as the drivers are dumped, but then they have to buy, fuel and maintain all the Johnny-cabs and delivery trucks themselves, which is currently handled by their drivers/serfs. So suddenly they become a capital-intensive high fixed cost business, probably still pricing very aggressively.