Berlin is not really as conservative as the rest of Germany, especially that so many foreigners live there which makes it seem so much more progresive and is not representative for the whole ~80 million people country but is more of an outlier (even Germans will tell you that Berlin isn't very 'German'). If you go to smaller cities the situation is vastly different.

In Austria I only see cash being exchanged at the supermarket and when I see someone paying by card or, God forbid, phone or watch, it's most likely a foreigner form another country where cash payments are not popular rather than a local who went cashless.