In the Netherlands you learn the traffic rules (at school) when you're 10/11 years old. There is a little exam even. It's normal children start cycling unattended from that point.
However, children have been cycling attended since... when they are big enough to operate a bike that goes fast enough to do so (so say, from 5 years old.) Ergo they probably already know, in practice, how to operate safely in traffic.
When my parents caught me cycling home unattended during the longer school lunch breaks, and I confessed I've been doing that for most of the school year, they were like: "oh. Guess you know how to do that safely then. Carry on." I think I was 9 at that point. (It was a very safe route, which is common for Dutch home-primary school situations.)
The EU enforces a less strict interpretation of NN. The Netherlands stricter law was therefore overruled with a softer version.
This came to light when the ACM (The Dutch FCC if you will) fined T-Mobile for applying a zero rating on music streaming. T-Mobile argues in court they are allowed to do so by EU rule. The Judge agreed.
As far as I know country law can be more strict than EU law, is that not so? In that case, the stricter law could not have been overruled with EU laws.
When my parents caught me cycling home unattended during the longer school lunch breaks, and I confessed I've been doing that for most of the school year, they were like: "oh. Guess you know how to do that safely then. Carry on." I think I was 9 at that point. (It was a very safe route, which is common for Dutch home-primary school situations.)