statistically shouldn't all that stuff should cancel each other out so nobody is really being unfairly scaled down. If more people pick the "easy" subjects and don't try in those subjects in addition to less of the "dedicated students" choosing not to do those subjects due to the inherent stigma- obviously results in it being easier for students to do well in them(getting higher percentiles).
Theoretically maybe, but I don't think it has worked out that way (at least not for HSC, can't really comment for VCE). In comparison to English Advanced, English Standard has a much lower percentage of students getting band 6s despite being "easier". When I say that the scaling is affected by too many students who don't try, I mean the type of students who don't try in any of their subjects (you're more likely to find one of these students in an "easy" subject, than you are in ext. maths, physics, etc.), not only that specific subject. A student that just doesn't care about the HSC overall. This is going to have an impact on scaling - even though it may be easier for a student to do well in comparison to the bludgy students in a subject, they may still be dragged down when compared to other subjects with more competitive students - you often have to get quite a high mark in a lot of these subjects to not be affected (and since many of these subjects are actually quite hard, this isn't always easy). This is just my interpretation of the scaling/ATAR system though, which as we've established is pretty confusing aha