With landlines one has an obsolescent technology. If something were to take out the landline grid, then it would not be rebuilt except for highly-specialized purposes. Prime example: after the Second Gulf War that took out the Iraqi telephone structure, the Kurds in the autonomous (and effectively independent, anti-fascist part of Iraq) went practically 100% cellular. Such was cheaper, safer, and more reliable than land lines. Reliance upon demographics wedded to some obsolete technology implies a distorted sample.
Normal consumer use is not one of those specialized uses. Reliance on landlines will soon be as obsolete as using pre-recorded VHS tapes for entertainment.
Wireless technology is never more reliable. Landlines are the way to go for quality and reliability. They are not obsolete yet and will not be obsolete for many years to come, if ever.
