Gymnastics is also good example. Some routines are just banned, because there is possibility of damage or too high risks. And it is quite fair as long as it is clear upfront and everyone follows the same rules.
That regulations are more in the line "we don't want participants to die or get crippled on live TV". Because gimnastics are absolutely insane for your body, the number of people who end up with totally destroyed knees, shoulders, ankles... before their 30's is horrifying.
