The network exists for non-pooled rides as well. Riders don't have to wait as long if there are more drivers, and drivers don't have to drive as far to pick up a ride if there are more passengers. The increased efficiencies allow prices to be lower as well.
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.
Upstarts will lose a lot if they offer shared prices without matched riders.