It is factually wrong. The correct way to phrase it would be that anyone can commit moral hazard and sign up for a public plan in response to a sudden need for medical treatment. So insurance can be available in a way that defeats the purpose of insurance systems.

However:

1) This is not free

2) This is not likely to save you from enormous medical costs

3) This is about on par with filing taxes. Probably easy to do if you understand the basics of whats going on, but few people do.