It's one thing when you're a fit adult male and get hit by an idiot cycling recklessly on the pavement, it's another if you're a small child or frail through sickness or old age. I've seen a couple of very near misses that would have ended very badly for the pedestrian through no fault of their own.
Saying this it's mostly teenagers in the idiot role from what I've seen and they are reckless by default.
Although the truly reckless ones are now on their ~50mph tuned illegal scooters with a "yolo" cheap lithium battery.
Those things are terrifying. Someone's little scooter's wheel base is definitely not stable enough for that sort of speed.
And that's before the battery fires.