I think you're overplaying the angle of brain rewiring to learn how to use a phone. That was just learning how to use a tool like any other. A very different thing is using a tool that makes people feel physically sick.

My guess is that people will prefer to avoid a chance of feeling cybersick when they can just use some other form of entertainment / display that is guaranteed not to cause any sickness, even if the device is superior when it works without side effects.