The bandwidth allocation is dynamic. During times when the network is busy, users have less. When the network is less busy, everyone’s limits are higher.

Also, your usage is measured across a week, not one day or a short burst of time.

As far as users with a lot of SP not using it all, that is kind of how it is used today. It assumes that the majority of users are not actively using their bandwidth.

The way it is setup and why is explained in the bluepaper.