For better or for worse, no, they could not have kept the working bits the same. The US EPA has progressively tightened restrictions both on what refrigerants can be used and how much electricity can be used. Instead of focusing on making that reliable, they're focusing on making it cheap so they can add gizmos.
Besides, if you've got to replace a fridge every five years now that's a win for the appliance manufacturers. Although, really, who offers anything more than a 1 year warranty anymore? That should tell you how long these things are expected to last.