In my father's time, and most certainly in my grandfather's time, everything you mention would have been simply classed as "common sense." Unfortunately, common sense is no longer common.
I went fishing, hunting, skinning rabbits etc. as a child with my grandfather. Also, everyone had a well stocked larder in their homes, and the means to defend same. People were mostly "self sufficient" and able to live off the land. We grew our own crops and vegetables. We milked our own goat.
Slowly, over my lifetime I have seen these skills and liberties eroded and forgotten in place of convenience and superstores and credit systems.

I was living in Cyprus in 2013 when the entire banking system collapsed, so I saw and experienced first hand what can happen to a first world economy.
Remember, Cyprus was a thriving country, the "back door" entry to Europe for many Russians and others; and a major international banking island

Within a few days of the banks closing their doors and the ATMs running out of money, people were back to bartering and IOU notes, if you could get them.
It was staggering how quickly society resembled a medieval model. I fear many, many people will be caught sleeping if they do not heed the warnings and advice in this type of post.
Like you say, no-one needs to go overboard. Just sensible precautions and backup systems in place.

I would like to also express my amazement at the resilience and restraint of the Cypriot community and people in the face of international isolation and their abandonment by both Europe and Russia. Although voices were raised in occasion in anger, there were no riots, and people helped each other as best they could.