This is one of the more ill-informed tweets. How hard is it to roll out a ride hailing up? Borderline impossible. Especially for companies that have zero competency in service, software and marketplaces.
...which is part of why Audi bought Silvercar. This gave them a well-run service company with physical locations in most metros. And they've recently added renter pickup so it's not like this is black magic.
What's more unrealistic to think is that a move to driverless cars / less car ownership would lead to the manufacturer's rolling over.