But that is the thing - in Germany or Switzerland 6 years old go to and from school unsupervised. The expectation is that they can in fact play alone on the street.

Do you have 6 year old in Germany today or are you talking about your own childhood? My 6 year old went to school on his own a few times and he was the only kid in his class to do so. He now no longer does as the teacher scared my wife into thinking it's dangerous to have him cross the street on his own (it's a small street and the entire way is 5 minutes walk).

I talked with my wife and we do want him to start going alone again when he is a bit older, maybe 7 or 8. But no other kid in the lower grades does (I went to school on my own from ± the very beginning as far as I can recall).

I have friends and relatives in Germany and in Switzerland. This was standard and recommended by school in Germany.

In Switzerland, going alone started even sooner - at 5. But, the school was assigned in such a way that kid did not had to cross bigger road, kids had reflexive vests and there is regular back to school campaign targetted at drivers with "inexperienced kids on road" message.

From my experience this is not common today in Berlin (although I know it used to when we were kids).