InvalidError :
Where are you going to find enough spectrum to provide everyone with wireline-like speed without having to make individual cells so small that you would need cellular masts on nearly every other building? The build and maintenance costs would be unsustainable. Nobody can do it even if they wanted to, it is practically and economically unfeasible.
Wireless technology is moving towards directional wireless communications which can "focus in" on signals coming from a certain direction. MIMO is a good example. Using 2 or more antennas, it can use a different multipath route between source and destination as an extra transmission channel, even though it's at the same frequency spectrum.
The ultimate will be phased array antennas, which allow a receiver (and transmitter if you know where the intended recipient is) to electronically "point" the antenna in a certain direction. Once you move to point-to-point wireless communications, most of the spectrum limitations vanish.
the engineers from phone/cable companies have admitted many times that data caps are nothing but a cash grab. they have explained numerous times that the network could easily handle multiple times more traffic than they face. about the only place the network is truly taxed is in very crowded cities like NYC. but they have even managed to get enough in place to handle the loads they ask for.
I can't speak for phone, but if you compare cable Internet prices with the price for an equivalent dedicated line, it's priced about right. e.g. An OC3 (155 Mbps fiber) costs about $20k-$45k/mo. Go with the lower price since we're talking wholesale. 155 Mbps * 1 month = 50.95 terabytes/mo. At a 300 GB/mo cap, that's 170 customers you can squeeze into that single OC3 line. $20,000/170 customers = $117.64 per month per customer.
Or put another way, you don't expect everyone to hit the 300 GB/mo cap. So you charge customers $80/mo and put 250 customers on that single OC3 with a 300 GB/mo cap. As long as average utilization stays below 204 GB/mo per customer, you're ok. (FWIW, I'm on a $60/mo 100 Mbps plan with a 700 GB/mo cap, so my cable company is actually charging me significantly less than this. If I were to actually use all 700 GB/mo, my consumption of an OC3's capacity would be priced at $275/mo)
So no, their lines can't handle multiple times more traffic. The price is about right. Where the cable companies are gouging you are in channel bundles and set top box rentals.