Really? I thought 100 was average, and 5 point below average makes you worthless? I remember reading that below 80IQ people didn't function too well, and below 60 they really are not able to do anything
Dysfunctional behavior begins early - typically by age 13.
Too true a former boss's kid went down that route and he started at age 12. The kid was not dumb in the low IQ sense, but by 13 he was stealing from relatives and friends to buy drugs, and by late teens he was jailed several times for theft. He openly bragged to his father who spent big time in the rehab swindles that he was able to get drugs and use them in the expensive rehab centers to which he was sent. I lost touch with the dad 14 years ago. I suspect the kid is either dead or in jail for something serious by now.
These people are those to whom HRC referred to as deplorables. Of course, she really meant middle class whites of all IQ levels, but was appealing to her racial identity base to cast aspersions on everyone in Trump's camp.
As you say, while an IQ of 100 is average, it was only a few generation ago that those around 90+- could still fit within societal expectations as being self sufficient working adults. Go back further, say 150 years ago, and labor intensive agricultural (ie 90% of the population lived on farms) requirements had places for people with even 80-90.
That's why I used 95 as a current threshold - people @ that level who work hard can still lead productive lives, but they won't really ever be able to enjoy any kind of financial independence or economic security.
Perhaps the key issue is that no one gets to choose their parents; whether one is intelligent or dull is really just dumb luck. And at the rate technological complexity is increasing, what happens when the average of 100 becomes threatened? Plus, does it stop there? No way, it keeps moving up the scale, which is why robotics and AI will eventually threaten to displace the professional classes.
Which brings us back to the vices ie idle fingers are the devil's workshop. Everyone seems to be noticing a large increase in homelessness. No, it's not just because Trump is president - it's really happening. Ditto for alcoholism, drug addiction and substance abuse. And the reason of course is that there aren't any suitable roles or places in society for these people.
It is, however, the role & responsibility for people who understand these issues to not be caught up in dogmatic arguments, but look at it logically from a policy perspective. How we deal with it is just one of the many burdens we share in being responsible managers.