Earlier quoted context omitted.
No? I’ve been mountain biking for over 20 years and never any broken bones or had to go to hospital as a result, despite doing downhill, trials, and dirt jumping. And I have 20 years of fitness to show for it - that’s about as positive as it gets.
You haven't addressed the argument (riskiness of the activity) with your anecdote.
For society only; what's the TCO of a mountain biking injury times the rate of injuries, over the TCO of obesity and depression times the likelihood a sedentary lifestyle results?
without access to that data, his anecdote does appear to be a stronger argument than literally no data, no?