Would a IGH drive train last longer than a derailleur drive train?
A chain used in a single sprocket configuration should outlive a chain used in a derailleur system because it always runs straight between aligned chainring and sprocket.

A 1/8" single sprocket chain will last longer than a 3/32" derailleur chain because it has larger bearing surfaces between pins and bushings.

A cassette is likely to last longer than a single sprocket because wear is spread over multiple sprockets. Same applies for multiple chainrings on a crankset.