Someone correct me if I'm wrong, but there appears to be a resurgence in the use of IGHs. I think for the reasons you originally mentioned. They are low maintenance and durable. Also, the gearing is protected from the elements. I have 2 bikes with IGHs. One has a 1974 SA AW3 and the other is a more modern SRAM i-Motion 3 speed. They both work great.