Yes, travel is not a total solution for all 300 million people, but think along the lines of many packaged tour companies in cities who cater for international travellers and can arrange such facilities very efficiently. (I once had dental work done in India, and people don't realize how easy it is, the same kind of thing that you get here.)
There are plenty of businesses trying to offer more accessible medical services also. Urgent Care clinics are becoming popular in New York City, where I live.
None of this is doing much about cost though. The Walmart style sells things cheaply that are allowed to be sold cheaply. They don't sell what they are prevented from selling due to regulations or due to non-viability of offering the service due to staffing limitations. The Urgent Care style is going through the private health insurance system like just about every other medical care provider.
So I suggested an insurance "startup" because the space that seems to lack innovation is the payment side of the health care industry.
meaning what? that a VC funded startup should come in and start offering health insurance? what are you suggesting? what does disruption even mean in this context?
let's get away from those corner cases where it's even thinkable to fly to Dubai for surgery. that's a high cost intervention for specific (wealthy) individuals. that isn't solving the problem of providing health care for 300 million people. how do you propose we do that?