Why aren't people just going prepaid? Cheaper and no headaches.
If there is any disruption to be had, it is an MVNO that is plugged into all US carriers, as well as satellite offerings, with the ability to pivot around whenever a carrier tries to squeeze the relationship. Google Fi with more carriers and better customer support, Airalo, etc. This enables you to keep your number while the service underneath the account can shift.
The prioritization is pretty straightforward, there’s a good reddit post that keeps track: https://www.reddit.com/r/NoContract/comments/1cyfjpp/data_pr...
So if the big three are able to set new [higher] price standards for their own customers, eventually they will increase wholesale rates for third parties piggybacking on the network. This will of course eventually trickle down to prepaid/MVNOs.
One of the many reasons why the Sprint acquisition was anti-consumer.