An obstacle isn't going to magically pop into existence the moment you mount a bicycle. Car-centric road design can indeed be dangerous to cyclists, but that says more about the road design than it does about the concept of cycling. Build better roads and cycling isn't dangerous!
And the problem with removing cars from the city center is that many users still need cars, either because they have families, or because they work and need a motorized vehicle (e.g a plumber).
> 35% des cyclistes tués, 63% des cyclistes blessés gravement le sont dans un accident sans autre véhicule impliqué.
35% of cyclist deaths, and 63% of cyclist seriously injured occur in an accident with no other party involved.
Another graph in that report shows that a vast majority of cyclist deaths occur while cycling for leisure. I would hazard that most cycling in cities is utilitarian.
OK, cycling at 50km/h in a city is dangerous and stupid (if you're even physically capable of doing so, which few are?). 30km/h in suburbs / 20km/h in the centre is mostly fine, and 10 for busy complicated spaces.
30km/h is slow enough to prevent the vast majority of crashes being fatal, and 20km/h will avoid most serious injuries.
I broke my wrist by falling from my bike when I was younger, almost while stopped (my wheel got blocked in a tram rail).
(Before we even consider that - at population level and in developed Western countries - lack of physical activity, and an environment which actively suppresses it through sheer indifference if not outright hostility - is likely inflicting a far greater burden on childrens' health and wellbeing than trauma).
But I guess she's just a statistic, right? Pedestrians, out of the way!
[0] https://www.leparisien.fr/societe/blessee-par-une-trottinett...
Source: me, who commutes by bike daily through a capital city.
I'm a huge supporter of public transit, but cyclists are a common enemy for everyone: cars, pedestrians, public transit-takers, other cyclists.