I kind of picture the cellular telcos doing this. Maybe buses and trains come with wifi hotspots allowed to connect. Otherwise auto passengers could use their devices offline, maybe read an ebook or something. Not the end of the world.
If they really wanted to push this they could do it directly in the baseband chipset and bypass the OS entirely when deciding to lock down the device to some kind of "travel mode" with limited functionality (such as no texting or no browser)
Not that I'm advocating for that sort of thing, but it's good to keep in mind that we don't really own the cellular devices we pay for and that even in the rare case we have root we can't stop them from doing what they want to our devices as long as they control the closed hardware.
I agree with the other poster about this being more workable in a fictional society with different shared values.