If I recall food delivery wasn't the only duty a delivery driver had. Between deliveries drivers were working in front of house, in the kitchen, food prep, and cleaning. They were employees with a scheduled shift and not contractors trying to gig on it.

The restaurant I regular order it's family run and either the father or son will deliver to us.

What we have now is a lot of abstracter layers of services, payment processors, workers, cloud computing, and VC. All these layers add a cost in an industry that can't afford the overhead. Unlike software and services, restaurants are high capital, high labor intensive businesses with low margins.