Sure. Due to difficulty (and possibly other factors, but almost entirely due to difficulty alone), different HSC courses scale very differently. It basically means that an aligned mark of say, 80, in two different courses of different difficulties would yield very different values contributing to your ATAR (rightly so). Take Visual Arts and Maths Extension 2, for example. By using an ATAR calculator such as Talent 100's [
https://www.talent-100.com.au/atar-calculator/], you can see that an aligned mark of 80 in Maths Extension 2 would correspond an ATAR equivalent of 97.65, whereas an aligned mark of 80 in Visual Arts would correspond to an ATAR equivalent of 58.90. These mean that if all 10 of your units scaled exactly like an 80 in MX2, you'd get an ATAR of 97.65; same for Visual Arts but an ATAR of 58.90.
Anyone can get a decent ATAR regardless of the subjects they do, but the best scaling subjects are: Maths Adv, MX1, MX2, Physics, Chem and Econ, and maybe Bio, Legal studies and some of the harder language courses.