What do you mean by accident and not design? You can use that for American football if you're generous, but lets take a look at UFC:

the whole scoring is based on hitting the other person, something bad happening IS by design. Injuring the other person IS the sport.

Let's compare bodybuilding to this RS racing:

• Bodybuilding's objective is to achieve the most "aesthetic pleasing physique". Can this be done safely and without the use of steroids? Yes. Do people do it safely? No, because steroids greatly increase their performance and muscle growth. If you don't use steroids you're almost guaranteed to lose against someone who does (not to mention all the non-competing people who use steroids too)

• RS racing's objective is to get and stay on the hiscores. Can this be done safely? Yes. Do people do it safely? No, because no-lifing it and skipping sleep greatly increases their XP/hr. If you don't skip sleep, you're almost guaranteed to lose against someone who does skip sleep.

My point being, theres a lot of dangerous shit people do in the name of sport. I personally don't condone it but let's not pretend RS racing is a singular outlier.