Dunno about the US, but where I live (Czechia, in Europe), voicemail is simply not a thing. I've never used it in my life and I don't know anyone who's ever used it, young or old.
We have it here for mobile but by default providers set it to "call waiting" instead. One of the reasons people don't use voicemail (other than not knowing it exists) is they charge you money to leave a message. Your plan minutes don't count. They probably charge you to listen to messages too.