I don't think self driving cars were part of the original Uber plan. It was bolted on after it became pretty obvious the business isn't sustainable. Uber was a behemoth before they did any self driving RnD.
You give an extremely charitable explanation. Given what we know about Kalanick character I doubt if your explanation is reasonable.
Uber's public launch was in 2011. It only offered limos, at rates competitive to traditional limo services. This would have been a sustainable (albeit much smaller) business.
Uber didn't start offering unsustainably cheap rides until mid 2013, when UberX was launched. Its self-driving research program was announced not long after in early 2015, so it's quite plausible that a long-term pivot to self-driving was indeed part of the UberX business strategy from the beginning.
Uber’s only path to levels of profitability commensurate with its VC valuation in 2013 that wouldn’t have involved self-driving cars would instead have required that the demand elasticity for taxi rides be so low that after getting people Ubering everywhere, Uber could successfully raise prices above the level of the taxi services it displaced without demand falling off a cliff.
Although Kalanick probably believed Uber was just that good, I doubt his investors did.
You give an extremely charitable explanation. Given what we know about Kalanick character I doubt if your explanation is reasonable.