Ok, that seems reasonable. What's confused me is the variability in trial difficulty because there are some that, I'm ngl, are really easy and I finish in 2 and a bit hours, and serve as ego inflators, while there are others that I can't even finish on time like the James Ruse ones. Also, is it just me, or do HSC questions just hit different to trial questions? I feel HSC questions are way cleaner and more intuitive, even compared to reputable school's trials like the SBHS and SGHS or even their northern counterparts. I think Baulkham hills is closest to reflecting HSC, except for maybe a few qs.
Firstly, trials are supposed to vary in difficulty. The purpose of an exam is to place the students taking it in a ranking order from highest to lowest. An exam thus needs to be tailored in difficulty to the cohort taking it. The HSC's cohort is all the students of the subject in the state whereas a trial's cohort is only the students at that school. An exam for 100 students where the cohort averages 85% raw is not a good instrument for ranking the top end of the cohort. An average of 30% is similarly poor as a tool for ranking students.
Secondly, because the trial is meant to grade the cohort taking it, while the purpose includes preparing for the experience of the HSC, it is necessarily a distorted reflection of the HSC. The content may not be the entirety of the HSC course as the school may not have completed the course. The more difficult questions may push the boundaries of what the HSC might ask because the trial may need to skew more difficult than the HSC.
Thirdly, the amount of time that is put into writing an HSC exam is truly staggering. I know someone who served on an committee writing an HSC exam and the time involved astonished me. It is unrealistic to expect a trial exam to be as polished as an HSC exam.
Fourthly, the skills of exam writers varies between schools and between teachers at a single school. Considerably. There are genuinely badly written exam questions, exam solutions, even entire exam papers. Just looking at 2020 papers, there are questions that appeared on multiple papers where the solutions provided varied. There is a particularly broad variation in topics that are new to the syllabus. The proof topic in MX2 has considerable scope for imaginative questions and the extent to which the HSC will explore that will only become clear over future years.
Finally, looking at a broad range of trials is wise, but don't get too concerns about the variation in standards and styles. Just use them for developing your own skills.