One of the problems is that, currently, having earbuds in is a social signal of "please leave me alone and don't try to strike up a conversation with me", such

One of the problems is that, currently, having earbuds in is a social signal of "please leave me alone and don't try to strike up a conversation with me", such as e.g. you might see someone on a train with earbuds in, and you know that means they don't want to be bothered.