How many people do you know that have replaced a personal car with Uber? I’ve known two people like that, and everyone else I know uses them in place of traditional taxis.
I use Uber/Lyft as a replacement for cabs to/from the airport, but almost all of my other usage of them is in replacement for driving my own car into the city. (In other words, these are trips that I'd otherwise take, but not via taxi.)