If they don’t know what it’s like to live homeless, to have their heart broken, to watch a loved one suffer and die, to face death, to face their own death, to work hard and fail, to recover from a horrible mistake, to live with a burden on their conscience, to be addicted, to quit an addiction, then they are not truly human. Not in the sense of someone who has seen any of the above. They can have no empathy with hardship because they have no idea what’s hard about it. They can fake compassion, but it the fakery is shallow and obvious and usually has the effect of making people feel worse. Oh, yes, and it's fake.
People who have not suffered are morons when it comes to pain. They cannot recognize it, and deep down do not believe that it’s really there. Overt anguish looks theatrical, anger looks like a lack of self-control, despair is weakness. It’s all melodrama. Suffering is, to them, a Hollywood production. All the suffering in the world is distant and vaguely unbelievable.
The inexperienced are not truly human in the sense that they are unfinished. They have not been made complete by life. Invariably they are boring to talk to, pompous, trivial, with absurd priorities, and an inability to fully understand all but the most basic parts of being sentient. They are cold and unsympathetic, but not from malice, rather, from ignorance, from complete oblivion to darker realities.
If you have not overcome something, if you have not been swallowed up by pain and emerged from it, if you have not entered into to battle and survived to come home, how can you consider yourself a grown up? In what way are you different from an infant, pampered and protected by its parents? What exactly do you know about yourself or have you gained from being alive as long as you have been?