That's not the case at all.
Telling someone that being fat is unhealthy isn't being a dick.
Telling someone that you lost a game isn't being a dick.
Telling someone that it's not okay to fail basic education class tests isn't being a dick.
It's called the truth - and some people may not want to hear it, but stating that it isn't the truth CERTAINLY doesn't fix the problem.
So lets just say we go full snowflake - no one ever gets to be told they are fat and/or stupid (be it insultingly or truthfully). What is the end result?
The end result is what we have today: The soft biggotry of low expectations. Problems are only increasing, not being addressed. But hey - someone's feelings didn't get hurt from an insult, they just suffer from massive depression and take pills all day. That's better though, right? OH - You say you're still having problems? Well here - take some more pills! Surely those will fix the massive gaping whole in your heart.