> ISPs have cost structures that scale with actual usage. Cables and routers have a fixed maximum capacity.
In other words, they don't scale with actual usage, they scale with maximum capacity.
When you take your monthly cable bill and divide it by what it pays for, almost all of it is going to things that don't scale with capacity. Having routers that are ten times faster doesn't require you to have ten times as many staff. They don't use ten times more electricity. They don't require ten times more office buildings or utility poles.
If you take the cost of the capacity upgrade and amortize it over total usage during peak hours, it adds a couple of bucks to the bill for the people who use the most. But that's not enough to deter usage by so much that you don't need the capacity upgrade. You need the capacity upgrade whether you charge per bit or not. At which point the upgrade is a sunk cost and charging for usage is inefficiently discouraging use of a resource that is being paid for either way.
