"Large scale emergency preparations in the USA fell to the wayside long ago."
Not really. The preparations have shifted a little. It seems the government doesn't want to really encourage individuals to prepare the same way it did during the cold War, and to a certain point many individuals wouldn't care to anyways. I'd imagine a lot of that is to increase the reliance in the government and limit the number of people who have the resources to radicalize.
The government still stockpiles emergency response medications and has plans to distribute them. FEMA has all sorts of resources including COWs (cell on wheels) for communication. But really, communications are secondary for ordinary citizens. You'll still have emergency services who can communicate, hams (including RACE), and stuff like that. They're more worried about food, water, shelter, meds, and order.
On the personal side, we can just look at early covid. People were freaking out and panick buying. It wasn't a big deal for my family. We were raised to have about 2-4 weeks worth of food on hand and just rotate your stock as you buy new stuff. Whether it's a pandemic, storm, production issue, or attack, it's pretty good advice. It can even help if you lose your income suddenly.