The problem is that even in streets with no risk for bikes (on way, low speed limit), bikes ride the sidewalk. And why would bikes have the priority over walkers, endangering them in the process? The weakest has the priority. You're ok to threaten my kid who's learning how to walk because you feel unsafe on the road? I don't see how a bike riding at 25km/h is innocuous for pedestrians at 4km/h. You're just behaving like a car driver, accept it.
I rode a bike in Paris for 3 years, and it's as hostile as it can get for bikes. Never had a problem,never rode on a sidewalk. Why? I know how to behave with cars. I stop at red lights. I ride in the middle of the road to prevent them from overtaking me dangerously. I'm speedy and I can keep the pace with a late taxi driver if needed.
This kind of reasoning confirms that indeed, bikers are not reasonable and bikes should be forbidden on sidewalks.