Yes, you are a result of your past, whether you want to admit it or not. What kind of past that was and how you choose to deal with it is another matter.
There is no need to attack every person who mentions having a hard childhood. Nobody's using their upbringing as an excuse. But if they manage to see how certain things in their past have influenced their current personality/behaviour, good for them. It helps to move on and change things you don't like about yourself.
If those things really did happen to you, I applaud you for overcoming them and succeeding in life. But there is no need to act like a tough guy and belittle other people.