There are no absolutes. Yeah, maybe the bylaws prohibit sidewalk riding, maybe they don't. When I am riding with my 10 year old whose bike handling skills may not be as good as mine and with situational awareness of a ten year-old, I have not problem riding on the sidewalk with him. He rides slowly. It makes absolutely no sense for him to be on the sidewalk riding 15 kph, which is perfectly legal around here for a 10 year old, and me riding on the road at 15 kph next to cars doing 50 or 60. When we encounter pedestrians we slow down, and sometimes right down. We ring our bells when we approach from behind. It just makes common sense. At slow speeds we are slow enough to be able to react to cars backing out of driveways, cars making left turns and right turns, and any unexpected movement by pedestrians.
When I ride on my own, and on my road bike, and trying to keep up speed I don't ride on the road for all those reason stated above.
I think this guy sums it up pretty nicely:
https://www.outsideonline.com/239811...g-on-sidewalks