If we are going to get to a modern set of transportation policies and regulations, we're going to have to acknowledge that the world we live in isn't perfect and people are making voluntary choices to travel. As long as airlines are appropriately disclaiming or giving disclosure and providing the consumer with the ability to opt in or opt out, then those are unfortunately the choices we make to travel in the modern world.
As to why we have set this border between us and the United States, it's terribly unfortunate, and it's something that may take decades for us to unwind.