If they were able to solve it through various methods that sort the components that could be used/recycled/sold who would finance the startup cost which would be huge when starting from scratch. Then to have it being more efficient than any modernized country would have their citizens scrambling for the same sort of facilities.I have a solution for the Maldives, if they're going to burn the trash, follow some European nations and burn the trash to make energy. The local conservationist was right, just dumping it on an island is no solution. Sweden only sends 4% of their household waste to landfills.
As for which environmental problems get more attention, one that's global in nature will always receive more attention than local ones. And as far as media is concerned, it fits their model better if they can present the story with two contrary opinions. Most people would agree that this dump site on the Maldives is horrendous and a problem that should be solved.
Other than some exotic toxins that is how anyplace handled it in the past with the exception that the 'poor and homeless' would pick through the garbage so very little ended up there permanently. Now scavenging is outlawed so the dumps are bigger for the same population. All the old cities of the world are still operating, some may have a slightly lower/higher incident of a specific disease or length of life is shorter.
What are you going to do, kill a city of people to save a bird sanctuary?
Even those floating piles of plastic in the ocean should be able to be skimmed onto a ship and the material taken for reprocessing. Hopefully the birds and such will learn over time to stay away from certain things.