This law was prompted by an accident where a person driving children in an electric cart crossed train tracks into the path of an oncoming train, and 4 children were killed.
Electric 2-wheel scooters would be perfect for a lot of places in NL - places where there is already a shortage of bike parking, and places where if you park and lock your bike outside, it _will_ be stolen if it is halfway nice. At least with a folding scooter, you can take it inside with you easily. Plus you can take it onto a bus, which is not possible with a bike.
Normally the Dutch are pretty thoughtful about their approach to laws, but this one just makes no sense.