What percentage of population? 5%? In mean time, people buy used cars for the amount of down payment, if not less. And do oil changes themselves because it's cheaper.

There're already services that cater to those people. Full-service car leases, regular car sharing etc. People who want that already use them. But they don't seem to get that wide adoption. If shared autonomous cars would be adopted as widely, they wouldn't change traffic flow much.