It's way easier for Tesla to start an self driving fleet with an App than Uber to get into car manufacturing.

Lyft partners with GM that acquired Cruise and their tech is solid. They are making cars will all the sensors built in, not add-ons like Uber.

Also Uber is losing a shit ton of money. Tesla is not profitable but doesn't bleed that much money.

Depending on how Waymo vs Uber goes, Uber may have to shut down their self driving car program temporarily. Stealing 40,000 files is ridiculous.

Add that to fact that they didn't get a proper licence so they don't have to report crashes and their self driving car crashed pretty bad.

Uber is a risky bet.