I can tell you that as a driver, about ~25% of my ride requests in Toronto are Pool requests.

We also have Express Pool where you get picked up / dropped off at some walkable distance from your actual origin/destination to make it even cheaper for the consumer and more efficient for drivers.

At one point Uber was even competing with the bus / streetcar with a special ride type where you would have to be picked up or dropped off at specific points along one street but they discontinued this.

I would definitely consider these sorts of shared rides as a moat.