In many cities, two-wheeled vehicles are required to not be on the sidewalk. I'll bet parent is equally annoyed by being almost run down by bicyclists while on the sidewalk....

I absolutely hate when bikes fly past me on the sidewalk.

You can rarely hear them coming (I don't wear headphones or anything), and they'll zip by with enough speed to cause serious harm.

What if I had stepped to the side? Or done a stretch and moved my arm to the side?

I'm not trying to be in physical therapy for a year or more because you can't walk your bike from the nearest corner to wherever you intend to park it.

All true. Bicycles can go 20mph, vs pedestrians' 2mph. Not a good fit. Scooters have to be even worse (heavier, worse collisions).

Faster than that I have see bikes going more than 20 in London - and blasting through junctions at a read light.

I assume they would be required to use bike lanes in most American cities. I am concerned about the liability involved. A local journalist here in Austin was hit by a drunk guy on a scooter badly enough to dent her driver-side door and render the door inoperative. Then he claimed she hit him. His auto insurance, if he has any doesn't cover his usage of electric scooters.

So she was facing a liability for fixing the car, perhaps some sort of insurance fraud on his part, AND her insurance was going to list an incidence of her "striking a pedestrian." Fortunately she found out there was some CCTV footage that exonerated her, but all of that just so some drunk a--hole can zoom around on a scooter and the scooter companies make money?

It sounds like it's the exact same situation as if they owned their own scooter or bike and crashed into the car.

How does it typically work if I am riding my own bike or scooter and something like this accident happened? Most people don't carry liability insurance for their bicycles, skateboards etc.

If you get into an accident, call the cops. If the other party is drunk, they'll definitely make note of it.

If you make a claim and the other party doesn't have insurance (it's unlikely the law requires someone to have liability insurance for their bike) and you need to make a claim, you could be SOL, but that's really a problem with how insurance companies operate.

Have some empathy. If something almost ran you over a few hours ago, it's perfectly normal to have a visceral dislike for it.

As far as requiring these things be in bike lanes, it's all well and good to say that. But at least in my city, there seems to be a ton of confusion from bike riders, cars and pedestrians alike about what the exact laws are, let alone reliable enforcement of these laws.

Cops are rarely going to see misuse anyway, so that wouldn't have helped the parent poster.