Austria, Switzerland, Uganda, Botswana, and Bolivia are also land locked. Paraguay has it better than any of these countries because of Paraguay's ocean access via the Paraguay River.
Then, there is Guayana. It is on the ocean. But I have no idea if Georgetown is capable of serving modern container ships.
Government policy can destroy the wealth of a nation.
Another idea is that a certain population density is necessary for take-off, e.g. Hong Kong & Singapore. Paraguay and Guyana 'just don't have the population.'
Along the thoughts of population required for 'take-off,' has to be the consideration for 'population density that will cause a crash.' Will Peak Oil cause Hong Kong and Singapore to crash? Or can those kinds of places survive as high tech centers on the downhill side of Hubbert's Peak?