Your family members have done very well, no doubt due to a combination of skill and hard work, though I suspect that not everyone who followed a similar path was as fortunate.
I do agree that university education can be a wasted investment for some and compounding the problem even further with post graduate studies doesn't guarantee employment as you can end up over qualified for some jobs and not good enough for others. My son found this at each stage and yes he was fortunate that it all came good in the end. It was certainly a worrying time. The PhD process itself is stressful as you can put in years of work and come away without a PhD being awarded. I've head of several instances where the standard of supervision was lacking. My advice to anyone considering higher education is you need to choose your subject and your university with care to stand a chance of getting value for money in terms of lifetime benefits.