It might work out that way in low income families, but looking at East Asia with it's share fair share of middle class and upper middle class with relatively secure future, there are still many known cases where the kids are pushed hard to enter the best (and highly competitive) school through private tutoring in addition to school as well as extra-curricular like private violin lessons etc. Those don't come cheap, and if the motivation primarily personal financial security, some of those expenses are questionable.
I am partly thinking about tiger mum's. Though I note that not every case will break a child, even those who went through such upbringing unscathed note that they know others who have cracked (goes back to the ability to handle stress being a case by case thing).
I am reminded of a TV show where some troubled teens are sent to some strict host family abroad. Sometime the teens get "stressed out" because they can't do whatever they want. I tend to be not so sympathetic towards that. But at the same time, I can understand how some people get more stressed than others over exams, for instance. I have found myself in situations where exams has affected my sleep, appetite and other things, yet at the same time I can probably jumping off high places (with a rope or parachute attached, or riding a snowboard) better than many.