I'm assuming you mean data (3G, 4G, 5G), text, and voice. No, you can't immediately post your video of you twisting a lion's tail or other stupid safari tricks, but the phone isn't useless.
Doesn't the camera still work? You are claiming that you can't take pictures and videos that the phone can store locally?
You are claiming the phone memory won't work without being connected to a network? It's impossible to download pictures from a camera for backup?
You claim the phone GPS won't work without a cellular network?
You are making the claim that e-books stored on the phone are no longer usable without a signal.
If you don't like books, I suppose you claim some games will no longer work off the phone network?
I can't use a local text editor to take notes for review later?
Please explain why none of these things will work. These don't even need WiFi to function!
I gave you some examples of things that can be done "off-line" yet your reply above suggests I'm wrong. Please explain further than your 4 sentence reply.
I returned from the UK a couple of weeks ago, and I chose not to get international service on my personal phone. I did everything I wanted using the free hotel WiFi after work- chat with friends on WeChat andother apps, used skype for voice. While good internet via WiFi isn't common while the original poster is on Safari, it shows what can be done without a cellular signal.