I don't mind responsible people who obey the law to enjoy them. However, where I live in NJ we have a problem with kids and illegals riding them all over the place at high speed and not obeying any laws.
They don't wear helmets and I almost hit one at night. He had all black on and no lights on. Thankfully they are cracking down on them.
Soon they will be required to obey the same laws as motorcycles. They will be required to have a license, registration and insurance.
This is the way it was with mopeds. These e-bikes should be no different in my opinion.