Shared experiences. These help you learn to socialise: you can talk about what you watched and heard last night on television with a wide and local social group. You feel closer to your community through having shared things to discuss and learn the skills to operate within a social group. Without this you feel isolated which leads to depression.

It seems to me, with modern technology, things are shared amongst people to create shared experiences and discussions but these are not people within your local physical community--leading, again, to isolation and the dangers therein.