The problem though, is that scooters have terrible dynamic stability in comparison to bicycles which thanks to conservation of angular momentum and large wheels, are very easy to control and remain upright on when traveling at speed. In contrast, even small things like hitting a small rock/bump the wrong way can destabilize someone on a scooter and lead to an accident.

Falling off a bike/scooter at similar speeds obviously ends with similar results, but I'd be confident to wager that the probability of an accident is a lot higher on a scooter due to the point above.

> I'd compare falling off a scooter to be similar to falling off a bike

I agree, and I've fallen off a bike a number of times. I have a few scars to show for it, and I would probably not be here if I hadn't worn a helmet during one of those accidents.

You very quickly reach speeds on a bike, and a scooter, where going down is going to mean significant injury even with the proper gear. Without safety gear, you're looking at life-changing or life-ending injuries.

Eh - I've fallen off a bike twice at relatively low speeds, and both time I've broken a bone (first time a finger, second time a scaphoid fracture).

I think it's important not to under-react just because the speeds are lower than a motorcycle - all those bones in our limbs break just as well at 10mph. When on a bike or a scooter, scaphoid wrist protection and at least a jacket on at all times, for me.

What about the danger to pedestrians hit by the driver of a scooter?

The risk is lower on a scooter than on a motorcycle. We don't have to over-correct though, and treat scooters like they're _that much_ safer than a motorcycle.

The most dangerous thing we can do is let ourselves mentally relax when we're on one, as if we're not on a big sharp chunk of (relatively) fast metal and inertia.

A helmet wearing person slamming headfirst into the nape of somebody's neck at 15 or 50 miles per hour is probably going to kill them.

  The risk is lower on a scooter than on a motorcycle. 

On the road, yes. But motorcycles don't routinely take the sidewalks.

The pedestrian won't hear the scooter coming.

Bicycles powered by humans are "helmets only" mostly out of necessity. You're generating a lot of heat, and things can go really badly for you if you're working up a sweat in full motorcycle gear.

Well, talking about the weight of the vehicle is a red herring here. With the exception of getting hit/crushed by the vehicle, the human component of going down is all about speed, fleshy weight, and ride-height.

I'm also not expecting people to ATGATT while on the scooters, but without doing that, injuries are definitely going to rise with increased use.

Yeah, I've gone down on a motorcycle at a low speed and I crushed my foot. On a bicycle it would have just been scrapes.

I stopped motorcycling after that.

I agree, but think of the change to Valley culture. Everyone wearing leathers or plate armor jackets. Full wrap face helmets and MBP's at all of the eateries. Eventually we could see roving gangs of electric biker faangs with their corporate emblems displayed widely across their backs. Soon territory disputes with comments like "Get outta here, crapple!"