Telcos report costs going down 40% to 60%. That allows T-Mobile U.S. & Sprint to offer "unlimited" with only a few gotchas. Competition and regulation will determine who is actually served.
Technology on the market can deliver 10X to 25X at reasonable cost; Weak competition or weak regulation could hold this back. Speeds over 50 megabits with a cap high enough to watch 100 hours/month of HD TV can be delivered in most of the developed world. The engineers can deliver. Marconi Fellow Paulraj tells me Massive MIMO will bring many of the same benefits to most rural areas, including in emerging nations. Extreme rural areas - the last 1-3% - may not be as fortunate.
Giga LTE offers about a gigabit to the cell site. Beginning this year, phones with a good connection will get 100-300 megabits down. Phones on the cell edge and behind walls are seeing a 4X improvement as well. Gig LTE combines more antennas (4x4 MIMO,) more spectrum (60-80 MHz,) and more bits squeezed in (256 QAM.) Gig LTE is five or six times as much as LTE started at and about three times the capacity of most advanced systems in 2016. The meter in the picture showing about one gig at Huawei's BBF in Tokyo Nov 2016 is Gig LTE. Two gig has been demonstrated by British Telecom. Explained for non-engineers here.