Services like UPS Mail Innovations are for bulk shippers that don't care when their stuff gets to where it is supposed to get to and UPS/Fedex do all the work of sorting and transport until the last mile. In exchange they get a cheaper rate. It has nothing to do with remote areas. UPS would still deliver there, just not with the UPS Mail Innovations level of "It'll get there whenever" service. I have received stuff shipped via Mail Innovations and I'm certainly not in a remote area.
Those partnerships aren't about UPS or Fedex not delivering to every zip code, but a slower and cheaper service than UPS or Fedex Ground...a service for bulk shippers like those of catalogs.
Even then it is completely irrelevant. I was shipping a priority mail parcel to Waco, TX and it took 10 weeks. I don't care what planet yer on, that is insane. The USPS can't be trusted with time critical anything.