I don't think it's that ridiculous that when you first introduce something so potentially dangerous and disruptive that you require a driving licence demonstrating at least a little about the rules of the road, as well as experience in traffic and also that you only permit scooters that have been built to a known standard and that are actively maintained and easier to ensure that they meet the rules on legal max speeds etc.
What is the alternative? Tonnes of youngsters weaving in and out of traffic on their £5 knock-off import?
Completely unfounded but I think there is a lot of pressure being applied by the taxi groups to try and discourage them.