There are other ways to discriminate, but not many have been actually tried to my knowledge.

One place where I worked studied a model with peak-load throttling. If you're trying to stream 4K video and the network isn't congested, you get full speed. If the network is congested, the subscribers who have been less active during previous peaks get priority and others get throttled. (Actually this was some years ago, before 4K video was a thing, but it's same idea)

Another model I remember studying involved charging for "time using the service" and not "number of bits transferred." This is similar to how voice plans have "anytime" and "off peak" allocations of "minutes."

So there are people thinking about this (or at least there were several years ago), but I'm a little surprised to not see any trials of alternative arrangements.