Part of the reason why many people (particularly geeks) dislike talking on the phone is that it forces both sides to be present at the same time, instead of allowing a user to consume or respond to the information at their own pace — or multi-task while they are doing so.
Ingram is talking about synchronous vs. asynchronous communication (ie: phone vs. e-mail or text) and how the proliferation of different kinds of communication technology has allowed people to develop different affinities for communication etiquette (depending on age/industry/how connected you are).
Both are interesting reads. The bottom line is that people have different preferences and we need to keep that in mind when we communicate with each other. Bilton, for example, writes of his distaste for communication that wastes your time (ie: leaving a voicemail when you can just send a text). Ingram, in a similar-but-different example, writes of the patience we need to develop for those who might not be at the same technological level we are (ie: don’t expect your parents to text you if they are just getting used to e-mail).