The reason I said being left after school as a nine year was too young and part of a wider picture of neglect for me, was nothing to do with not being trustworthy or responsible and everything to do with regularly having to deal with things all alone as a small child for an extended period of time.
I was badly bullied at school. I had a lot to hold in all day, and no safe person to talk to at home. Being told you should end your own life for a bulk of the day, then walking into an empty home and not having a soul to talk to or comfort you for an extended period of time was awful. Not having any way to emotionally regulate and not knowing how to cope with the feelings of exclusion and rejection was hard. And I felt pretty abandoned at home. Just me, crying again, sometimes physically hurt, and no one who saw or cared. A very clear message that I didn't matter.
Upsetting things can happen at school and it's good to have an adult to help you process it, or just to listen or ask how your day was, can help. All I learned was that I didn't matter and I needed to bottle everything up. I was also left to deal with bailiffs at the door because of an unpaid bill during my parents' divorce. And followed into a fast food restaurant 5 mins from home where I'd been given money to buy dinner, and sexually assaulted in a toilet there. I didn't know how to deal with that at 9. I didn't really understand what had actually happened, or that it was a crime. And of course, straight afterwards I went home to an empty house.
And we were a middle class family. I had a SAHP who liked to spend their afternoons and evenings mooching around in town...that's why I was going into an empty house, not because of work commitments or as last resort to make ends meet.
By 12, I was far better equipped emotionally to deal with things. And I could easily take myself off to play with friends, or into town on the bus, or to a park or hobbies. Much better than being stuck in a big old house alone with a lot of sadness and just my feelings.
Of course, my parents would have described me as a mature, resilient child with no issues.
Looking back, knowing that there was an ASC for a very small fee that I could have attended, I can't understand what the rationale was. Character building, I suspect. "Aren't we good parents? Our child can be left and is no bother whatsoever! Such independence!"