The problem is that bandwidth is a highly limited resource, just like real estate is a limited resource. Eventually we will complete saturate network bandwidth no matter what technology is used. This has been discussed in various forums for many years.
Eventually yes. Some media are already saturated (short wave), but in general, the terestrial bandwidth will not approach it's upper limit in our lifetimes. Terrestrial networks are limited only by the cost of putting down the infrastructure (fiber these days) and maintaining the equipment to drive it. A single fiber will of course have limited band width that will no doubt be reached in our lifetimes, but when that runs out, there's always more room in the trenches, and if there's a will, there's room for a new trench. As the existing infrastructure is paid off, and the monopolies which were granted for it's initial construction break up, the price of terrestrial bandwidth drops. There is no shortage of intra-continental bandwidth (at least not in populated wealthy areas such as north america, Singapore, etc). There may be a shortage of inter-continental bandwidth. The cost of laying undersea fiber makes it difficult for new competition to get a foothold and hence the market lends itself to de facto monopolies. brad