Does it really take 12 years to become a dermatologist ?

The time will pass no matter what you choose to do. Where do you want to be when it does? FYI, dermatology is one of the most competitive medical specialties. Work hard.

Yes that is about the length of time although @Carol is wrong in her assumptions. Your background makes very little impact on your progress through the stages. The progress from PGY2 onwards depends alot on where you are prepared to go. If you are happy to move location every couple of years (by this I mean different enough location to mean you have to move houses) you could be a lower level registrar and progress whilst someone "better" than you only prepared to work in the cities may have to take longer to get through the stages.

For sure, even if you pass all the exams, it's about the hoops they make you jump thru in Oz, unless you belong to an ethnic minority. AandTSIs get in because it makes the Uni look PC. Private school, parents doctors, ??? Gmsat??? I honestly believe that the whole system is to totally discourage the poor, who cannot afford to do volunteer work, and those who really want to be doctors for altruistic reasons, so the dogma and the status quo is maintained.