the funny thing they don't teach in these top school is that when you join them, you are already set for success. First of all, your parents have the money to pay for your education by avoiding the public school. The campus are better, teachers usually come from a more international background (which is useful if you want to work in these large corporate).
Now, they can also afford to pay for private tutors which is a big help. You probably have a maid helping you with everything and in general a bigger flat where you can study in better conditions. When you study you probably do not have to have a side job either so you have already all the cards in your end to succeed.
There is also this bias that if you made it to a top school, then you are way more intelligent than someone who failed by a few points. Maybe that person did not have all the help the well off kid got, was tired from the noise coming from the upstairs neighbor in these public housing.
There was a study in the US that said if you compared the student that got into a school by a few points, and compare to those who missed by a few points, they end up having similar careers, but there is still the bias and these school cast system.
Are these schools worth the price? In today's world nope. Look at how they coped with Covid, they had no digital plans on how to cope with these kind of situations, which shows you how bad they would cope as a business.
I have worked for the same company in the UK and then in HK. In the UK it was a mix of background and honestly I saw people who were grown up adults with real life experience, they all worked in the summer while studying etc... every time there was an issue they would trouble shoot it without crying and fix it. Some came from good schools, others not. You could not tell the difference in most cases.
Now in HK, HR had a completely different approach, they would only hire tier 1 university with International school background. The result was like working in a kindergarten. They were all acting like babies and you could see a lot of them did not even have to pay for their rent, it was just a job to keep mommy and daddy happy. Most would quit the moment it gets a bit tough, of course it's easy when you have a big net underneath.
Anyway, rant over. Do these schools prepare you for the real world better? I doubt. I was amused on how they don't even teach Excel in HK. I started learning it in school at like 15-16. Even learned the old Excel (forgot the name) in MS-Dos at 10.
I did graduate in a decent business school (from my own pocket), I am still trying to find what skills I learned there that I could not have learned in books or online. The only thing that helped was having that piece of paper for the work visa here.