alt Hacker News> speed limits are designed for the less than median "driver"
Which is a dangerous line of thinking, as everyone thinks they're above average.
Speed limits are also, to some extent, designed around physics. Higher-speed accidents have more kinetic energy.
I put the "driver" in quotes: it is not just about ability (let alone perceived ability), but also about equipment (car braking power, tyre quality in relation to road conditions), attention and driving style. You can be reasonably and objectively above average just by having great tyres and strong brakes paired with average attention (which you can control too) and average style/ability.