Who would do the necessary training and licensing, the company selling the product, the local council or a government test centre. Then there will be the usual comments about costs?.
I have a mobility scooter (in reserve for that day), my late brother and sister in law both had a mobility scooter, but both just couldn't get on with it. My sister also as one, and only recently she had another rider of a mobility scooter ride into her, causing damage to her mobility scooter, The offender simply drove away, stating that they had no insurance of money, so basically it was tough luck. That cost my sister, or at least her insurance £600 to put that incident to rest.
So something as to be done, but what and by whom?.
And please don't tell me it might be discrimination?.