I'm British and we had to learn all the European capitals. Decades before the internet became part of daily life, mind (we had encyclopaedias instead).
Is it still useful? Yes, Id say so. A basic level of general knowledge still comes in handy unless you want to be consulting your phone all the time just to keep up with a conversation. Much like learning the times tables. Having the answer instantly to hand is a lot easier than opening up a calculator app.