I don’t remember much about how I learned to use the telephone, but I do remember how I was expected to speak on it. My parents made sure I learned to be as polite as possible when answering the phone. I was taught to answer the phone with “Hello?” and ask to whom I’m speaking if they don’t immediately ask to speak to someone specifically. If they did ask for someone, I would ask them to wait one moment and then get whoever it was they were looking for.
On the flip side, I was also taught to deny sales people. If the caller ID said unknown or blocked, and I could hear the sounds of a call center in the background, I simply said the person was unavailable and hung up.
Outside of using the phone, I think that how I learned to use it made me more polite in person. It made me realize there was a certain level of manners people were expected to behave with when interacting in public, and I learned to be as polite as possible.
Ironically, despite how polite I am when using the telephone, I actually hate it very much, and sound of my cell phone ringing annoys me.