Re: vendors are working on this right now
Vendor propaganda to make mobile operators spend more (e.g. Three who don't understand).
Unless your infrastructure is rubbish, then the bottle neck is ONLY at the air interface. The backhaul has to be able to manage full peak base station traffic anyway. If your Base Station is only using copper or ancient Microwave too slow (modern microwave and fibre can feed easily 5 to 10 base stations) then this is like lipstick on a pig.