I grew up in a time when there were no mobile phones. That definitely had its advantages, especially when you were on vacation. When you were away, you simply weren't reachable. Nobody expected an immediate reply, and the world kept turning just fine without us.
Today, I use my smartphone for messages, emails, authentication for other services, photos, appointments, navigation, games, and my finances. It's hard to imagine everyday life without it.
Simply put: back then, many things took longer, and that was perfectly fine. Today, things often can't happen fast enough.
RE: who needs phone?