We still say that the phone was ringing off the hook. When's the last time you used a phone with a hook?
I remember when I was a kid we used to have a phone on the wall and that it had a hook that the receiver hung on. If you picked up the receiver, the hook would move up and would engage the dial tone. If you put the phone on the hook, it would move down and would disengage the phone.
Let's not be in a rush to change the terminology, though. I still like it. We still say we dial the phone, right? When's the last time you used a phone with a dial? :-)
What other old phone terms do we still use?
Let me think and then add your own.
1. We still talk about wiring money. While wires may be involved, most wiring is now done through the internet.
2. Phones ring but no longer contain actual bells like in the old days.
3. We hang up the phone even though we normally don't really hang it anywhere. We normally put it down somewhere, not up.