Today mostly is all digital, some landlines came via 3G and 4G. And I’m doing the whole concept simplified.

Old times yes, it was all wires. Btw, calls between cities was hell. You pick the phone, says that want to talk with City B, City A operator telegraph to City B to connect you with then, if that connection exists then you will be connected to an operator to City B and then being able to “make the call” and sometimes there is a delay.