Rides being more dangerous at higher speed is universal, not just to individual.
If a bike is designed & geared at the factory to be ridden at slower pace, changing the gearing for faster riding is simply inefficient and dangerous.
Like I said in my previous post, there are plenty of other bikes that can go faster more efficient.
Folding bikes are just not meant (and inefficient) to be ridden at sustained higher speed, that's not limited to each their own.