Re: who's responsibility?
I think this demonstrates what I expected, but you did allege that I'm assuming something that doesn't represent you, so let's give it a try. We can limit ourselves to the talking on the phone bit, because it perfectly demonstrates what I was talking about. I see your post as assuming why people don't talk on the phone: "fear of talking on the phone rather than some form of texting (thus taking away their "shield from emotional vulnerability")". That would appear to me to be a rather clear generalization, even though there are lots of reasons why people avoid talking on the phone.
Here's one. A change in attitudes, not because of any "emotional vulnerability". One change in attitude has come along because the phone is no longer the only way of contacting someone. A while ago, if you wanted to talk with someone, the phone was the best way of doing it, but now, an email or chat message will arrive just as quickly. Some people have grown less eager to use the phone because it means they have to have a conversation when the call happens rather than an asynchronous one at a time of their choosing. And that is recipients of calls. I have certainly noticed this. There are people I want to talk to who just don't answer the phone and don't listen to or respond to voicemails. If you need their attention, you have to send them an email and schedule a call if needed. That applies to many older people as well, and there's at least some logic in it because it is less disruptive to whatever else they were doing that day. That, in turn, means I'm less likely to call people because there's at least some chance that I am wasting my time because they won't answer or respond, so although I quite like calling people to communicate with them, I still generally start with an email.
That set of people are not doing that for anything related to "emotional vulnerability". Incidentally, what is your theory for why there is more emotional vulnerability on the phone? It's pretty easy to insult someone or to be insulted over text chat. There's more direct vulnerability on a video call, but those are rather popular.
However, just because that or other non-emotional reasons exist doesn't mean everyone is as I describe. There are indeed some people who dislike talking on the phone for some different reason. However, by making a statement like you have, you've ignored many alternatives, applied your own assumption for why people do things differently to how others did them decades ago, and then used your assumptions as evidence of a different problem with a tenuous connection. Even if we were limiting this to those who feel anxiety about making a phone call, we'd still have to figure out why before we could blame it on any particular change in activity, but we didn't get that far because I saw you lumping all sorts of things in.