> Wow, in the USA, we can get MRI's the same day or at worst case, week.

You can. And the cost is higher than almost anywhere on earth.

You can get them quickly in most places with a publically funded healthcare system, it’s just that a priority patient is very very sick and you never want to be that person.

Scarcity demands some means of rationing out the product. Setting higher prices is one means of doing this, so only those with some means of paying can get it. Another approach is via wait times, where only those who can wait and afford the time penalty can get it. There are other variations, but there's no such thing as a free lunch.