General Discussion

I walked 7 blocks to school by myself as a six year old first grader after the first week once I showed my Mom I could because she and Dad had to work. Mostly residential blocks, true, but but I had to cross the main four lane drag going through Santa Maria at the light like a Big Girl of course.
I was going to the store myself to pick up small items like milk or a bag of potatoes, or fruit by the time I was eight. My parents would leave an envelope with a dollar or two and a list for when I came back from school.
This was in 1965, 1967. And there were plenty of people driving like fools back then, too.
It depends on the kid. My oldest grandchild could be trusted to cross a street by the time she was five (and she has ADHD!), while my youngest grandchild is still distracted by butterflies and dead leaves being blown down the road at nine (and she doesn't have ADHD, so far as we can tell, just lives in her own bubble).

If the kid was four and by himself, I might agree with you. Might. A four year old probably needs to be monitored, they're still toddlers. By five or six, most kids are aware enough of their surroundings they don't need to be chaperoned everywhere.

Parental neglect is wilfully going on a two day bender or hareing off for a weekend to go to Vegas and play slots - leaving young kids alone without enough food, access to money, or making arrangements for someone who could watch out for them.
I helped the kidlet's friend parents as a backstop, like other parents in my neighborhood did while I was growing up. I was the "K's Stepmom", and Laz was "K's Dad" - who could be depended on to feed and watch over her friends when their Mom or Dad had to go out of town for a job or interview, because my parents had been there. Life happens. Accidents happen.

Not being a Helicopter Parent is not Parental Neglect.