i mean they were, if you got lucky.
If you were neurotypical; if you bought in to the local religious sect's particular flavour and embraced it wholeheartedly; if you followed the other local cults of sports fandoms; if you were lucky enough to either have family without their own trauma that didn't take it out on you OR decided to repress it in exactly the same way that they did and just simply passed it forward or didn't talk about it.
i don't know what the ratios are but a LOT of people fell through the cracks.
it's just that the birth rate was high enough to continue the population growth, and there were socially acceptable ways to ignore the inconvenient problems (see: https://en.wikipedia.org/wiki/Rosemary_Kennedy)
it's why there's now suddenly an influx of ADHD and Autism diagnosis - because in the past anyone outside of the norm who wasn't lucky to do one of the things above was simply ignored, beaten, or died.
now the stigma is gone and we're finding EXPLICIT paths to treatment, tolerance, and embracement of mental health, neuroatypical brains, spectrums, etc. Is there overpathologizing? Maybe? Hard to know! The stigmas still aren't gone. Go read the comments on any video providing tips on how to parent children on the spectrum and see neurotypicals freaking out about how soft the current generation is.
the western world seems to have peaked in tolerance in the 2010s, and is now backsliding into authoritarianism and fascism. that's trying to recreate a lot of those original support systems (by destroying the new ones). It's a bold plan, let's see how it happens.
I think you're understating how well those people were incorporated into society. My grandfather was born in the 20s and was described as quite "high strung", was amazing with technology, would repair anything, and even used to build his own farm machinery. These days he'd definitely be called severely anxious, and probably labelled as being on the spectrum. Yet he was part of a community, farmed his whole life, and built a family. People knew his quirks and compensated for them.
Would your grandfather have been so well integrated if his problems had not been offset by such ability?