As we progress, the fate of human kind becomes more fragile.
In the past where self-sustenance is possible, families/tribes provide for each other. They sew their clothes, hunt for food/rear poultry and grow crops, build their homes and shelters. Yet as we ‘progress’, these tasks get separated. A trip to McDonalds: someone rears our chickens, someone slaughters them, someone turns them into chicken fillet, someone grows wheat, someone manufactures the wheat into flour, someone ships all these to another someone who’s paid to fry those in batter and oil.
You pull out your wallet and where did you get your money from? From your banker job where you handle clients that incidentally include a large shipping company (your main client) and a main slaughter house handling chickens (which only makes use of that shipping company’s service)
In the past, if poultry in a certain farm (subsistence farming, rear chickens for own consumption) is infected with disease, only that certain farm would be affected, maybe a few around it might risk a few strands of disease.
Now, if anything occurs to that large slaughter house, many would be affected, including that shipping company. If that shipping company collapses, it would cost you your job. No more McDonalds for ya.
In the past, everything is chopped up— individual entities. Now, everything is linked and we’re aiming to further link the links together. Once a there’s an interruption to a link in the system, the entire system would be affected— effects large and small.
Once everything is concentrated, just destroy the source.
The easiest way then to destroy the human civilisation is to use a snip from apair of scissors where we’d needed many many more snips in the past.