AT&T is kicking off the 5G revolution with its launch of America's first 5G mobile hotspot on Dec. 21. Initially, this new network will only come to dense parts of 12 cities, and the millimeter-wave spectrum that AT&T is using is more suitable for cities and suburbs than for the countryside.

Rural areas won't be left out of the 5G world, but 5G will be different there. It will enable new ways of farming and living. It will be a big deal, and many of its applications haven't been invented yet. But it probably won't give rural homes unlimited high-speed access to Netflix next year, which is what rural residents probably most want and are most frustrated by right now.