I think one of the reasons for why Australia's maths curriculum is crap is mainly because maths isn't really "respected" in Australia and a lot of people dislike it, thinking that it's a 'hard' subject and often students will neglect it
That's why we have to offer general maths, because these ppl are not that "smart" enough that we have to do something in order to cater for their needs. Also this general maths thing, is what's causing our maths to be quite shit because it's lowering the amount of students which do 2U, 3U and 4U
I think one thing that needs to be changed in Australia is that we should start introducing some senior concepts in junior years (like calculus, locus and parabola) and eradicate general maths for good
I remember once (a few years ago) I was watching TV and there was this ad saying that the Australian government aims to get Australia in the top 5 countries in the world for academics and with this attitude to maths, they can't really do so
Another issue that's causing this "maths issue" in Australia is students don't respect the fact that they're getting educated for and just fck around with their education (not saying everyone does). The Education industry is one of those industries that I don't think seem to get much respect as the other industries do and we need to change that. I know for a fact teachers on a day to day basis need to report in students who don't wear the right uniform (at my school) but the end of the day, it doesn't matter who wears uniform or what, it's about whether or not the student is getting educated properly and the teacher is doing the right thing by educating them
tl;dr the government needs to start respecting the education industry and eradicate all those stupid kids who don't want to learn (and eradicate general maths and start introducing some senior ideas in junior years). That way Australia can become one of the top "maths countries"