The way to do it that respects freedoms would be through incentives. E.g. if preventative checks would save public healthcare a lot of money, then give people t

The way to do it that respects freedoms would be through incentives. E.g. if preventative checks would save public healthcare a lot of money, then give people that do it tax credits or literally pay them money to do it! With cars, there are greater third-party effects (i.e. your car failing and crashing into someone else), so it makes sense to require a certificate before one is allowed to use public roads.