I just read an interesting article on ExtremeTech about the growth rate of various technologies.
The conclusion I draw from this is infrastructure makes the technology, the electricity and phone took years (Electricity 0 - 10% 30yrs; + 10 - 40% 15yrs; + 40 - 75% 20yrs = 65 yrs) and (Phone 25 + 39 + 20 = 84yrs). Because cable had to be strung from supplier to customer, this is a time consuming and expensive process.
Wireless tech which has a much easier and cheaper install requirement, i.e. radio, TV, mobile phone and now smart phone; are much much faster. The infrastructure is much easier to put in place so it is put in place faster.
If some major catastrophe destroyed the mobile phone and fixed phone infrastructure, I doubt anybody would go to the expense of re-laying the cables to put the service back in place. Mobile phones would become even more ubiquitous then they already are.