Doomsday theories coming from people who make fame by instilling fear and anger are not likely the best theories. It's market-driven drivel with little merit.
For "prepping," I figure our citizens have to learn to become better problem solvers and more self-sufficient. There's way too much dependence on our various institutional and governmental infrastructures for us to effectively mitigate and manage any type of significant catastrophic event. Heck, even natural disasters are compounded because people simply aren't prepared to deal with adversity.
As for China, their survival depends on our greed. That's what got us into our position in the first place. Perhaps they'll take advantage of that, perhaps they won't.
As for communications readiness, perhaps thinking in the rule of 3s will help: have a plan, have a back-up and have a back-up for the back-up. That might mean multi-band radios, phones, smoke signals, semaphore flags, signal lights, etc.
They most important element is a community willing to support each other in various ways through the collection of individual strengths and skills. I'm more concerned about with whom
I will communicate that exactly how
I will communicate, but the how is still important.
If the communications infrastructure collapses sufficiently to take all the cable news channels off the air, maybe Americans of all political persuasions can focus more on fixing our common problems than dwelling on those things we disagree on...
That's probably the best quote I've read in a long time. More time focusing on skills, less time listening to people who get paid to elicit a reaction.