No, the education system does not need a major overhaul. What does need an overhaul is the mindset that anything less than an 'A' grade is an Asian fail. This mindset is killing everyone: kids; parents; teachers and so on up the food chain.
It is an unrealistic expectation of what it means to be 'normal'. In statistics, what we understand as 'normal' bunches up in the middle, tapering off at both extremes. When we take extreme position 'A' to be 'normal', the whole distribution shifts to compensate when the frequency of 'A' does indeed increase because now, 'A' has become too frequent to be 'normal'.
Many factors could account for the shift towards more kids scoring'A's. The biggest factor is probably the availability of after-school tuition. But while it does give a boost to the individual kid, the system suffers because too many kids sacrifice too much time on developing themselves into what they (and their parents) think is academically 'normal', and not enough time on developing their other facets that will make them well-adjusted, really normal people. And in the meantime, their collective academic achievement turns up the pressure on the next cohort to do just as well if not better, because if your older sibling could do it, why can't you? But the fact is, yesterday's goalpost has shifted further and smaller because too many goals were being scored, making the game unbalanced and unrealistic.
Some people see this continual raising of standards as 'progress', but in fact, just because more kids are acing their exams doesn't mean they have learned anything apart from how to score in their exams. Exams, after all, are games with rules, and once we understand the game of exams, we learn how to game the exam. Everyone out there in the marketplace, and frequently in the schools themselves, offers tips and tricks; methods and strategies; and game-breaking techniques that with enough drilling and when applied properly are likely to score the aspiring student the sought-after 'A' without needing to understand the subject even at the foundational level. And because the end result is an 'A', no one questions if any real learning has taken place or not.
The way back to sanity is to regain our respect for the 'C' grade and to stop disincentivizing failure. Once we allow our kids to bunch up at 'C', it does not mean we are settling for mediocrity, but rather we are accepting normal for what is realistic, and therefore putting an end to academic curriculum escalation. Exams can carry on as they have for centuries and still continue to deliver what they have been always supposed to deliver: providing a hypothetical controlled environment in which a student puts into practice what he has learned in order to demonstrate mastery of the subject being tested and to receive correlated feedback therein. If there's any competition in the system, it is against one's previous efforts and not against a fellow learner. Accepting a 'C' grade tells the student that there is more to achieve, a further step to take. There is forward movement when you dangle a carrot in front of a donkey, and none when the carrot is already in its mouth.
The main concern we have today is how to tell if an 'A' grade a student has scored is the result of real learning or just from gaming the exam. A simple rule of thumb is to ask how the student acquired the knowledge. If it was acquired without question, it was probably taken as doctrine, memorized, rehearsed, rehashed, and learned for the sake of the examination. If the student questioned the material (you can always check the quality of questioning); failed it often and showed slight increments in progress over time (big jumps do happen, but they are rare), most likely we are looking at a student who really does know his stuff.
Because questions are such a big part of the learning process, we teachers, too, have to be mindful that in our eagerness to teach, we do not anticipate questions and provide answers before the kids ask them. One sure-fire way to kill curiosity is to over-inform -- which we tend to do a lot -- and take the mystery out of life, leaving them jaded and think they already know-it-all at such a young age. And also to not shoot down questions, assuming the kids haven't been listening (whomever can listen and get it right the first time?) when we have a curriculum to cover.
Exams are necessary to school-based instruction, but they need to be taken in the right spirit. The overhaul being asked for is for us all to put exams back in their proper place. To hold exam results as a predeterminant of human lives and their future is asking a little much from a measly scrap of paper that gets replaced by another over time in a person's life.