Yes, for a telephone currently it is simple, both as it is necessary for the user to be able to disable the 5G functionality, for legacy and usability reasons.

Yes, for a telephone currently it is simple, both as it is necessary for the user to be able to disable the 5G functionality, for legacy and usability reasons. However for a device such as a TV, once it is sold with a network plan arranged by the manufacturer, there doesn't remain much of a point to allow the user to normally control whether this connection is active. For a while, an option would remain to disable or configure such an option, but over time it seems likely that the user would no longer be able to control this directly. It gets even easier for devices such as a smart lightbulb or a smart toaster - devices for which there wouldn't be any direct user interface. Once these communicate via wireless wider-area networks, the trend seems to be clear.