Bullying is a big part of life, Whether you are in school or working at a job, You will always have to deal with bullies. If kids are always protected against bullies, They will have no clue what to do when they face reality. Im not saying we should encourage bullies but parents should definitely encourage their child to take care of it themselves by talking with them, Confronting them, Etc and should only intervene when the situation starts to escalate. Obviously the child's feelings are gonna be hurt but in doing so, They will learn a life skill and not grow up to be a snowflake.
Being bullied is a big part of why I got into bodybuilding and I am very happy I did. I think it depends on the person and the situation. For some people it ruins them and for some it strengthens them. That is not to say it is ok to bully someone, However.
The only thing it accomplishes for the bullied person is to have a lower self esteem. This might even be so bad to the point where the bullied might become the bully in the future. It will make kids more ashamed of themselves about the thing or things that they are being bullied for.