Both rideshares subsidize about half of what they pay drivers, but their deficit is not nearly half of their total revenue. Take out the drivers, profit tomorrow. Patent good for 20 years. That's about as juicy as it ever gets.
And regarding patents: what will probably end up happening with self-driving patents is that there will be a bunch of different entities (everyone currently working on self-driving tech) that will cross license their IP to each other. A patent in this space is going to be good for licensing fees, but not for giving yourself a monopoly on self-driving tech.
Approval? That's another matter.