- have no "buffer", meaning living in houses where you can't store food in quantity sufficient for a certain, not little, period of time, in some countries there are even official recommendations like Swiss who recommend one week of food and three days of water (I think, not sure about exact data);
- live in a not-united population that can arise effectively, no government, no power can stop an angry population, they can only try to avoid communications, create confusion and divert anger towards against false/others target.
The first issue might be sorted out if economical conditions allow citizens to live in large-enough homes with room for freezers etc to guarantee even a month of autonomy. The second unfortunately is a tricky business that can change in decades, no less...
There are plenty of examples of the government doing just that in China. Boxer, taiping, 8 trigrams rebellions, etc, and those are just a few recent historical examples.
In a country as large as China, you need substantial support from sympathetic government insiders if the angry population is even remotely regionally located. Uniting a billion people is an extremely high bar if that is your goal.
About sympathies consider that all armies in the world so fare are made of Citizens not drone, so they are humans against humans, a dictatorship can't count much about army loyalty under certain conditions, and that's one of the reason all governments that can push so much toward drones and isolated cohort of people, to avoid having a "social society".
As for hunger, the last mass famine in China was during the Great Leap Forward. Let's also not forget the effects of the Cultural Revolution.
I think you vastly overestimate the extent to which governments and populace form an "us versus them" mentality- it is rarely so simple as government on one side, populace on the other. At the end of the day, no matter who wins, someone still has to be in charge, and no large group of people will readily agree on exactly who or how.
As you rightly say society is complex, so we can't just simplify to us vs the enemy, not matter what, but humans needs are not that complex and human psychology is still essentially the same in millennia. The ancient "panem et circense" is still valid, just to cite one famous governing model still used today. The social ignorance and complexity is used by those who rule to grab and stay in power, but again with not really different principles than 1000 years ago, just means/tech/scale is changed.
Any dictatorship to remain in power need to satisfy enough his subjects and/or find enough justifications for those who aren't satisfied, that's why most dictatorship grow fast, giving back an apparent good/fast evolution then when resources start to be scarce they push toward war/blame opponent etc and again that's might last or not but in the end they fall. A new society rise on the ruins of the precedent. We are probably around one of those changes were wars can't work anymore alone. At those points populations rise, no matter how much united, they rise ad a big destructive force no one can resist.
The longer you wait, the hungrier you get. The hungrier you get, the weaker you are. Best for the people of Shanghai if they start rioting now than a week from now, when it may be too late.
Honestly food issues will be spread all around the world in the near future: we are too much for the food quantity we can produce, it's just a matter of time. Probably the key most élites count on are a divided population between a mass of young kept a bit nourished and well indoctrinated just to live for work, a small extent of "new feudal class" to keep the system app and other poor to starve. When (not if, IMO) we will be there it will be too late to change the course but I do not know how much late is already...
Definitely true. I just hope people aren't so tolerant of hardship that they miss their window of opportunity.
With respect to food shortages in the rest of the world, I'm not too concerned. Many items are missing from grocery stores in my corner of the world, but basic sustenance doesn't seem threatened. Maybe I can't find chicken one week, or cheese the next, but there is still plenty of beans and bread around to keep stomachs full and I don't anticipate that changing. In Shanghai, the food shortages seem to be to be the direct consequence of the government locking down the city and disrupting supply chains. It's not a food production problem, it's a lockdown/logistics problem. If the rest of the world doesn't follow suite with this sort of zero-covid insanity, then I think we'll be fine.
To push such big change in such short period of time just pushing fossils prices does not suffice. To steer whole populations you need a hyper big sense of catastrophe, no matter much if real or invented/enlarged. Try just reading Klaus Schwab's "The Great Narrative" and Mark Carney's Value(s): Building a Better World for All. Of course they do not directly say they want a poor population but it's clearly implied.
Lockdowns themselves can be read as a way to forcibly reduce consumption while keeping people under fear so obedient to a certain extent. Especially since they sanitary effect is evidently proved to be essentially null... If resources are scarce States need to isolate themselves from peers to preserve their scarce reserves and grab others states resources, so wars are needed but against enemies that can't defend themselves to reduce natural resources usage keeping number of deaths high. Remember that after the French revolution we are effectively in an era where economy dominate on politics, so decisions are made on purely economic considerations.
I hope your brother finds a way through this situation.