It's great that Uber changed the CEO and he's trying to change the culture. But that doesn't happen overnight. This is a 9 year old company with 12000 employees. It has a culture that has been built and reinforced over that time. As CEO, he doesnt make decisions at the front line directly, and it may take him a few years to convince everyone in the company to adopt his rules (and he may even fail, depending on the incentives inside the company). There's no magic wand a CEO can use to change a company overnight.