I imagine the downvoting is due to your erroneous projection of the customs of your locale to the entire larger world. Even narrowly considered, your links don’t really support your point of view (eg there are numerous shared pedestrian/bicycle paths in California, children are allowed to cycle on sidewalks in California, etc).
Riding on the road is even more dangerous in some areas, though.
If a cyclist and a pedestrian collide, someone might go to the hospital. If a cyclist and a car collide, someone is likely to die, and it's basically always the cyclist.
That kind of reasoning wouldn’t make me feel better if I were the pedestrian who had to go to the hospital. You make it sound like bicycles are just an inherently bad thing to have around :)
If we're fantasizing about eliminating some mode of transport, my vote is for cars. Most of my initial parent comment's concerns would go away if there weren't any cars, and pedestrians would be safer on crosswalks too.
In reality, though, we all have to get along. And those concerns are addressed by cyclists not riding at breakneck speed and going blindly around corners. I don't see either of those behaviors very often in my area.
It's worse now that Lime and other bicycle rental startups have littered the sidewalks with bicycles. When I'm not running around a bike left on the sidewalk, I'm getting run over by somebody riding one on the sidewalk.
I'm amazed at how often a bicycle rider on the sidewalk will actually warn me to get out of the way. I haven't knocked anybody off of one yet. It's only a matter of time before somebody bumps into me on one and gets hurt.
[0]: https://www.merriam-webster.com/dictionary/pavement