Here's my take.
I was a gentle kid, well behaved and sensible, never got into trouble at school. My siblings were all broadly the same.
My parents (well, dad) had been brought up in a brutal environment by no doubt scarred post-war parents. He was authoritarian and terrifying as well as deep down a very kind man. I had a genuinely miserable childhood, not all of which was necessarily down to this, but in part. My siblings and I all have various forms of trauma from childhood.
I am a recovered alcoholic, likely add, and have had various eating disorders all of which I've only recognised in adulthood. I've had loads of paid and nhs therapy, have struggled my entire adult life with crippling anxiety and am on antidepressants. Me and my closest brother both dropped out of uni. I recvered and restarted, sadly he didn't. I have nonetheless massively contributed to society through my job, worked ceaselessly etc. I've never been a burden to anyone but myself.
My siblings all have similar issues, mainly anxiety, but mine are the worst. We're all fairly driven and successful, but mental health issues are rife.
Fast forward to my children. I did attachment parenting, nurtured them, gently cared for them. They were not usually difficult children, I was very blessed behaviour wise. If anything they were too gentle. I was very kind and very soft mostly, and sympathetic to their needs.
In late childhood and adolescence they both went through extreme mental health issues. Eating disorders, extreme anxiety and phobias, social anxiety, body dysmorphia, mebtal health, school avoidance, suicide attempts.
I was at my wits end with it all and, predictably, one of my dds blamed it all on me and dh and became estranged at one point. I remained calm, learned about positive approaches to it all, forgave, helped, gave up work, and worked relentlessly hard to keep us all together. We eventually reconciled. We spent thousands of our savings on private therapy and we were gentle and forgiving.
I believe the difference will show in adulthood. Had I taken the tough love approach favoured by my parents generation, I think my kids outcomes would be far worse. Dd1 is now thriving at a prestigious university in a difficult subject and looks like leaving most of her MH issues behind her.
Dd2 is starting to emerge from her MH issues, and is taking a gentler route towards her qualifications so she has a chance to grow up.
All those years of gentleness I had doubts. There was a nagging voice telling me to take a tougher line, "toughen them up". I suspect if i had, wed be looking at major substance abuse issues by now and estrangement.
We sought to find out the root causes of bad behaviour in terms of pain and distress. My parents weren't equipped with that knowledge and they did their best. I have no regrets.