Ruth didn't have close to a 10 WAR season until he was 24 years old. Bonds didn't have close to a 10 WAR season until he was 26 years old. Trout doesn't even have to improve to be almost 30 WAR ahead of Ruth and 37 WAR ahead of Bonds at the same respective ages. Think about that.
Although that's also why I said if he improves -- if he improves and isn't injury prone he'll be the best player of all time.