A Facebook/Twitter account is basically an opportunity to publish your 'digital ego'.

Its the reason apps like Instagram exist- they allow you to polish your images so that you can basically tell the world, "hey look how much fun I'm having, and you're missing out"

Facebook/Twitter/ in fact a lot of these publishing platforms exist to weed out the mundane parts of your life so that what is public is the most exciting, jealousy inducing 'Cliffs Notes'.

Essentially, thanks to them, when you die, people will be able to look at your profile or your tweets and mourn, "that person lived such an interesting life."

Whatever you opine upon reading this is your answer to your question (as I see it)...