To clarify, multivariable calculus was a university course. However, yes, I did take OAC calculus in high school.
I guess I am pretty old, lol
Also remember the background was how necessary math is to the end of secondary school. Most math at the 17-18 age is University prep (algebra, vectors, calculus). If the desired outcome of Sunak's proposal is to educate society as a whole, then that stuff would be overkill.
I think there are quite a few patent troll lawyers that have those backgrounds, of course I've never investigated it, but just from news articles. Of course my main point is sci-tech grads being unproductive and reminding how patent litigation/strong IP laws are promoted as "fostering innovation", when most of the time it is the opposite.
Here in Australia the maths you can do in last 2 years of high school is basically divided into 3 levels of easy/medium/hard, people usually pick 1 or 2 of them to study. The medium difficulty maths has differential calculus while the hard difficulty has integration calculus.
My Chinese relatives are indeed pretty startled to learn that high school maths in Australia can reach this level as I think integration in China is Uni only, and it clearly doesn't fit with the image of western countries being weak on maths in high school. However I would say the hard flavour of math is definitely dropping people in the deep end and see if they sink or swim. You get a big point adjustment upwards for your uni entry point if you do well in the hard maths so it really sorts out the smart people from the masses.
Hilariously the physic I was studying in the last 2 years of high school has a lot of problems that deal with area under the curve (particular of note: calculating orbits using Kepler's laws) and obviously they cannot assume everyone who choose to study physical also studies hard maths, so all the "find the area under the curve" type question has grid already lined up for you to count the boxes. My class which is made up of mostly Asians who picked the big five subjects (english, medium and hard maths, physics, chemistry) would argue with our physic teacher saying this and this question provides us with enough information that it's both faster and more accurate for us to use integration to find the answer and he would go in a joking manner "no I don't want to see that here, you want to practice the Dark Arts go do it in the other side of the building".
I thought it was very clever to design high school course such that you learn both integration and encounter actual real life questions in physics that need integration to solve at about the same time. It left a deep impression on me on what Newton was trying achieve when he invented it. These days I've forgotten most of calculus from high school but I still have a very clear idea on what it's for and what it's capable of doing because of that timing in high school.
There's a series of sci-fi books called Uplift series which makes use of this idea as part of the setting. Humanity has joined the galactic community of smart alien races and
