A few points:
Cable will never fully defeat DSL, mainly because of business customers. Simply put, a business location is much more likely to have telephones than TV’s.
Those aformentioned businesses are not going to buy cellular service for every desk in the office when they can leverage a handful of landlines into an internal phone system capable of sharing the outside connections. land line phones also generally run on power provided by that land line as opposed to limited battery life, so for desk-bound locations cell phones make absolutely no sense.
Some businesses may be well suited to VOIP phone systems, but it is by no means a good fit for all or even most of them. And many that would benefit from it would do better to use it as their internal phone system and still use POTS lines for external calls.
Go to your local shopping mall and you will find that most of the stores have POS systems that communicate back to their home office. They are almost certain to have a DSL connection for it. It would not make sense for them to buy that DSL line and not use the same LEC for voice.
Land line telephones flat out sound better and last longer than cell phones, and VOIP carries its own host of expensive drawbacks.
As long as there are business customers, copper is not going away.
You must assimilate to the new technology. You aren’t supposed to speak of the limitations and failures of the digital world, whether it is substandard compression and artifacting on DVDs, digital television, dropout in telecommunications, or whatever.
By a new phone. You can play P!nk on it and be hip. Or play the new Jay-Z Obama theme song.
As for corporations, they can talk through the internet.
And all of this digital communication can be processed/monitored much easier.
You can get coax cable without hooking a television to it.
Those aformentioned businesses are not going to buy cellular service for every desk in the office when they can leverage a handful of landlines into an internal phone system capable of sharing the outside connections.
You can do the same with cell phone service or VOIP. Instead of your internal phone network connecting to a copper wire at the outside wall, it connects to a transmitter or coax.
Two things are going to have to happen for copper pair to go away. One is that unlimited call phone use is going to have to get cheaper than POTS for high-volume users -- and that's pretty close to happening. The other is that cell phone reception is going to have to get a lot better, more widespread, and capable of handling the load that will result from switching over POTS lines; that's gonna take a lot of towers.
For VOIP to serve the whole country, you're basically going to have to replace twisted-pair copper with coax or fiber, mile for mile, in every area that doesn't currently get cable. It'll happen eventually, but not quickly. I do like the point of the original post, which is that the programs designed to fund universal access would be better spent promoting the spread of coax than continuing to subsidize copper.