The factors might not go away. It depends on how the reform is done. To say that they won't go away is incorrect. You don't know this. As with all reforms, they can be done well or poorly.
Sure, in a magical world where we suddenly switch to a perfect utopian medical system, the problems will go away. But none of the concrete proposals in this thread will make the problems go away.
It's hard to claim that this can only happen in a magical world when there are numerous examples of universal healthcare that provide better outcomes with lower costs.