Are refrigerators really set to die after five years?
Not true in the USA. The refrigerant is all contained within the sealed system: compressor, evaporator, and condenser. While the life expectancy of refrigerators does seem to have greatly diminished in the last decade they rarely fail because of refrigerant leaks.  I am a refrigerator repair person and the majority of problems I encounter are defrost, air flow, ice maker, and control related problems.

My feeling is the target life expectancy for new refrigerators is 10-15 years but there will probably be a repair or two needed in that time.

Hope that helps some!