After intensive discussions in the past one to two years, the vision about the potential 5G and its enabling technologies seem clearer, based on observations in Johannesberg Summit. Seems most of the technologies are well known. The question is how to exploit them better to further improve the efficiency in utilizing resources (energy, spectrum, infrastructure) and adapt to more dynamic communication needs in as far as 2030. While no one can safely predict what might happen 15 years later, there is no upper limit for the desire to support faster, securer, and more reliable connections that are more cost efficient. How cost efficient the 5G is will determine how pervasive it is in 2030. The exponential growth in computing has been a driving force in reducing the cost in 2G way to 4G (more and more popular) and it can be foreseen that it will continue be one main driving force in the future until it costs nothing for computing. So complexity in 5G is not likely to be an issue and instead, the infrastructure, material, their maintenance would be.
Most of the talks at Johannesberg Summit were very inspiring and fortunately all of them are available on Youtube and in the playlist below. It will never be a waste of time watching them one more time.