What nonsense. I was in Berlin last month, the ticket buying experience is abysmal. The machines don’t work. Sometime (don’t know when) you can only buy tickets on the train since they don’t have ticket machines at every station. When you do try to use the machines it’s some ridiculous combination of zones and unspellable names you have to type out to get your ticket that isn’t intuitive at all.
In NYC, buy ticket on machine -> works for one trip wherever you’re going in the city. Outside the city? Just talk to the person at the ticket window and they tell you what to get.