I understand your argument Jonathon, and appreciate the significance. However, it's the EU's law that are in conflict, one not due to any specific country exclusion,
Transport matter policy belongs to the EU according to numerous treaties agreed by member countries, and the mandatory two and three wheel type approval law first introduced to member countries on 9th May 2003 specifies the exclusions from motor vehicle type approval. The only one relevant to us is the EU specified pedelec law, 250 watts maximum, function limited by continuous pedal rotation up to 25 kph (15.6 mph).
So S class e-bikes are motor vehicles needing type approval according to the EU, unless a country makes a specific exception. Since the S class e-bikes do not meet the requirements of the EU to be acceptable motor vehicles, they cannot be registered for use.
So the discrimination in law, if any, is not one of any nation but that of the EU itself, and it is for them to resolve it. The UK for example has not discriminated, such discrimination being forced upon it by EU order. It is not the duty of the UK, nor is it appropriate, for the UK to correct an EU legal error if such exists.
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