That's not a requirement of such a system, though; France has a dual public/private system, where everyone is guaranteed service at the public system, but well-off people who wish to pay extra can purchase private care.
That's true of the UK system too. People get public treatment, but can go private if they wish. There are some restrictions on novel cancer medications if those are shown to be both expensive and minimally effective. I don't know if it's a good thing that dying people are protected from high pressure selling of pharmaceutical companies or whether the government should just allow people to spend tens of thousands of pounds on medication that may not extend their life and may not improve (and may decrease) their quality of life for the remaining weeks they have.
