Walking also has health benefits and it doesn't significantly elevate the heart rate either. And it isn't true that ebikes are much faster than regular bikes. Ebikes power assist is limited to either 32km/h in NA or 25km/h and these are both speeds easily reached on a conventional bike. The difference is that an ebike can help a person sustain a comfortable cruising speed for longer distances, when going up a gradient, or against a head wind.
As someone with both an ebike and a regular bike, my regular bike is actually faster in some situations and slower in others. Faster going downhill and slower going up for one. The main thing the ebike accomplishes is that it encourages people to bike and get some exercise even when using a regular bike would be too slow due to things like hills or when they don't want to get sweaty. Times when I'd otherwise feel obligated to take the bus. Claiming it has to be regular bike or nothing because ebike isn't enough exercise is like claiming someone has to run to their destination since walking isn't good enough exercise. Well running may be very popular recreationally, walking is far more popular as practical transportation.
It also isn't true that ebikes are necessarily more dangerous. It depends on the model. My ebike isn't any heavier than the thick-frame mountain bike I had as a teenager, and there are plenty of conventional bikes nowadays that have a similar weight. Modern batteries and frame materials tend to be much lighter now than for ebikes 20 years ago. And it also depends greatly on the weight of the rider since the force experienced in a collision is based on the momentum of the total system (bike + rider+ any cargo). A 200lb man riding a 25lb conventional bike at 32km/h has far more momentum than say. a 130lb woman or teenager riding a 40lb ebike at 32km/h.
The idea of classifying ebikes as motorcycles makes zero sense considering that most motorcycles can reach (usually far exceed) highway speeds and weigh hundreds of pounds (average about 600lb). Meanwhile ebikes are assist limited below the speed of most city streets. And mine only weights about 35lbs and all the ones I've seen weighing well under 100 lbs. I think some people fail to make the distinction between bicycles that happen to have a battery and motor assist compared to the ones that look like a moped with barely functional pedals that only exist so it can be called an ebike. My ebike model below is most certainly not just called a bike because of marketing. Anyone would clearly see the difference between that and a motorcycle with the only visible difference being the battery.
https://www.touchofmodern.com/sales/...78e/daymak-ec1