for’a lot of’those procedures many go to good hospitals/docs outside the us and pay a ton less, even including flights and recovery.
If you're having a major surgery--a transplant, a THA, something big and costly--gettng on a plane and spending a fortune to go to another country might be an economically viable option. But if you need a cardiac cath right now, you don't have time to get on a plane to have it done. If you need a Mohs reconstruction for skin cancer on your nose, it's not worth going abroad; it's not typically going to be done in a hospital anyway. But it is too expensive for the average person to pay for himself even if the physician reduces his prices dramatically.
I'm unenthusiastic about medical tourism. For most major procedures, I want my surgeon and team a short drive away so I can be followed easily. Go to India to have a mastectomy and you're 12000 miles and a lot of hard traveling away from the guy who would need to follow your cancer case. Not practical.