Support what you are saying LG.
I do not believe there is genuine bias according to state.
I believe there is a natural bias towards age. Unfortunately for QLD they are at a disadvantage where the starting age / length of schooling is different and the Year 12 average age is around 16.5 years as opposed to most other states having an average age above 17.0 years.
Giving away between 8 months and over a year in physical development at this age is enormous and therefore the older players are at an advantage on average.
With the changes to the QLD school system put in place in around 2006 or 2007 with a Prep year being added to the curriculum this age bias disadvantaging QLD will disappear in 2019. About that time you will see the QLD Schoolboys teams being even more competitive
There are still a number of players in the QLD team who are turning 18 this year. This is because they may have originally been from interstate, deliberately started a year later by parents, repeated a school year or went to TSS who have been aligned to the NSW Schools System with regards to starting ages for quite some time.