The example is a bit contrived. That doesn't change that there are a number of scenarios where you want to be able to have granularity. You don't necessarily want to pay 24/7 for low latency for video calls, bandwidth to stream a VR movie or software updates to run at night.
The ISP game isn't exactly fair as is. The average person have to get a fast connection just so they can get decent access to the services they are already paying for or that is monetizing them.
Just how would that work across multiple ISPs? The application begs for a circuit.