Iain, this is a difference between a phone and a PC. A PC (at least in 2015) seldom has a SIM, and if it does it's typically something you plug in, so an always-present top-level "Cellular" screen would be an annoying stump. On a phone, though, you may not realize (for example, you may have forgotten) that it doesn't have a SIM, so the in-place explanation is useful.
Hopefully by the time we adapt this design to the PC we'll have a way of telling whether the device has a SIM slot, not just whether it has a SIM.
Iain, this is a difference between a phone and a PC. A PC (at least in 2015) seldom has a SIM, and if it does it's typically something you plug in, so an always-present top-level "Cellular" screen would be an annoying stump. On a phone, though, you may not realize (for example, you may have forgotten) that it doesn't have a SIM, so the in-place explanation is useful.
Hopefully by the time we adapt this design to the PC we'll have a way of telling whether the device has a SIM slot, not just whether it has a SIM.