This is an imperfect process, and there's a balance to be made. Sure, we can be too paternalistic, and putting too many onerous restrictions on things (or on banning things outright that people have a reasonable desire to do). I think banning motorcycles would fall under that. Sure, riding a motorcycles is far more likely to get you injured or killed than riding in a car, but I think most people would consider banning motorcycles to be too extreme.

It's not fully objective. We're emotional humans, and that's ok. We're going to do things that are risky, and some people are going to get hurt or killed doing them. But that doesn't mean we should just throw up our hands and give up. We can still make it less likely people will get hurt doing those activities by requiring some safety measures must be taken.

Alternatively the control could be given to insurance companies. For example you get a lower deductible in an accident if you're wearing a seatbelt (or bike helmet or whatever) compared to if you're not. Insurance companies actually calculate the risks/costs, as opposed to governments cramming something resembling moral judgement (or just blindly perceived risk reduction) as law.

It's certainly a slippery slope. You will find people who object to "their taxes" being used to do search and rescue, provide wilderness medical treatment, etc. for activities that they consider unreasonably dangerous, e.g. winter hiking up even fairly moderate mountains.