You don't know Destiny if you didn't face SUROS Regime when it was a crucible beast. You didn't know Destiny if you never experienced the loot cave. You don't know Destiny if you didn't actually go to Mars and farm relic iron for spare materials. You don't know Destiny if you haven't shot yourself in the foot in water and died. You don't know Destiny if you never had a time when you could wear whatever class item you wanted without light penalty. You don't know Destiny if you think Xur always sold the crappiest gear.