system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Since most communication can be done with a wifi connection, why haven't Internet service providers put cell phone companies out of business?

You really don't need cellular service in order to communicate nowadays with apps like Skype or Facebook calling. Why not make wifi the new cellular service?
gpt
The *whole point* of cellphone service, originally, was to ensure that you send send and receive calls from almost any place, even while moving around. You can't connect to the local coffee shop's wifi if you are in a car, for example, because you'll be out of range in mere seconds. Wifi doesn't have much range, and there is no common system for uninterrupted switching from one wifi provider to another as you move along.

You might ask "why doesn't someone just make a more powerful version that fixes these problems?" They have. It's called cellular.