They already had lyft line. That's not a cab model.
Not exactly but it is pretty "cab-like", in that the driver is still independent of the passengers. It's basically an easier way of sharing a cab.
Re:Lyft Carpool: A New Way to Commute
by techrat_hacker on Friday April 01, 2016 @12:10AM
(#11402545)
Lyft Line is cab splitting
I imagine something like this would be a lot easier for municipal governments to swallow, compared to the current "not a cab but yes it's actually a cab" model.