Somehow nobody mentioned market dynamics.
Your health is priceless. You'd pay anything for yourself or your children. Therefore the going rate will be whatever maximizes profits, which doesn't necessarily mean providing services to everyone (at least in backwards countries) but usually means providing service to "most of the community", more or less.
That's why when very few people are tourists, its profitable for the tourists. Obviously this doesn't scale because if you can outsource basically all non-emergency medical care, prices will rise for tourism because the served group now earns 5x as much so "why not" charge 5x as much if the locals don't go there anymore.
Its no different than "tourist-y" restaurants and stores. Once the locals are chased away, prices explode to what the tourists can pay, what the locals pay doesn't matter, they're kicked out of the market.
Once the real economic value disappears, all thats left are scammers. So "everybody knows" that going to .mx for raw vanilla, tequila, and jewelry is a losing proposition because so many crooks are involved. You'll hear accusations of this for medical tourism, but its just not there yet. It'll take awhile but the economic forces are inevitable, at which point there will be true medical disaster stories about scammers.