Most of those 400 million people never existed since thei existance was in numbers on a spreadsheet only.

How come all these populated areas are now deserted?

I would approach this question as cautiously as I approached "How come everyone in China are dropping dead on the streets" during 2020. Remember all those videos we were watching? Yeah, its all a psyop. Everything is a psyop.

Instead of answering as to how exactly the psyop is being spun, its far better to focus on what the goal of the psyop is.

When it comes to China, there are two psyops - the benign WH psyop to ease the economic realities of China to the world, and the CCP psyop to try and delay the inevitable and portray US/Trump as the villains.

My whole YouTube feed is filled with China related videos - and everyone is refreshingly original I have to say, even though most are complete rubbish. A lot of these people are becoming part of these psyops purely by their own emotions behind their strong held beliefs about China - be it China-loving or China-hating - I get both in equal parts, and both side are completely missing the real picture. Its very funny actually.

You mean Chinese GHOST CITES which have been around for decades?

Well documented

China had a one child policy for decades starting in the late 70s. As we know, Chinese value sons more than daughters (how many of us know Chinese here in the US whose first born is a son?). Naturally, as a result of this favoritism, there would be far fewer baby girls either born or allowed live in China, eventually resulting in a lack of women able to have children.

The Chinese must have known that because of their one-child policy their population would eventually collapse. How do they save face and avoid admitting that their policy caused this collapse? Create a pandemic, either real or not, to blame it on.

The ratio of deaths to weddings eventually would become high and peak at some point, so it is probably true that there is currently an unnatural imbalance, but it is being blamed on the wrong event. The Chinese can see this imbalance and they must know the real reason, but are being told that it's because of covid, not their government's former one child policy. Gaslighting on an epic scale.

Edit: Bubble's comment about China getting money from the IMF, World Bank, etc. - these organizations couldn't possible have been fooled into believing China's reported population count.

I would wonder first if the populated areas were really populated. Are they even built out? Are there even real kitchens, bathrooms, walls inside? My second question is, were there really 400 million Chinese people that recently died. I was in Junior High (now Middle School) in the 80's, and I remember hearing then about the one child policy in China. How are there even women around for men to marry? You know they killed their first born if it was a girl. So that's a good reason marriages are down. I bet Chinese women are hard to come by, and they make it look in videos like they are equal in population. Nope. Men have no incentive to do anything without women around. A society that is in collapse, and it's not because of covid.