I've thought about this for the past decade or so. It's obviously going to be many simultaneous factors for any type of decoupling this pervasive in society, but I tend to simulate things out in my head and here is what I've largely ruled in and out.

1. It isn't gross executive compensation. Holding everything else constant, executives are very good at negotiating the very best deal for themselves and corporations live and die by the law of the jungle. These two forces balance each other out. Higher executive compensation probably means that executives are more important than they used to be, which I would expect with an increasingly technological society.

2. That said, executives and the wealthy class pay way less in tax than they used to because they're less tied to a region which means they're less civically minded and they're more able to region shop for lower tax rates, leading to a race to the bottom.

3. Computers automate tasks that used to require a high school education. IBM is IBM because they started with cash registers before computers came along. There used to be a banker with a real education in every single town. There isn't anymore and we (especially we!) know why.

4. Communications—starting with the telegraph, but certainly not ending there—make locality irrelevant. Combined with the forces of capitalism (e.g., comparative advantage, re-invested returns) this hyper concentrates specialization.

5. Standardized shipping, especially sea containers. The Chinese government's greatest insight was the importance of physical freight and they leaned in hard to become the centre of the worlds manufacturing by essentially[0] subsidizing it.

6. Many decades of low interest rates, on the half-baked ideas of Keynesian theory of productive capital. Surprise! It turns out that injecting liquidity doesn't necessarily expand business activity. There's plenty of cash locked up in corporations and monied investors. They're desperate for return, but the hyper specialization issue stops them from getting alpha once they hit the market's carrying capacity. Instead these low interest rates go to...

7. Asset bubbles and arms races! Everyone needs a home. Everyone wants a good education at a prestigious university. People buy whatever sugary drink advertises the most. Inflation isn't really low. When a small family home in Toronto costs more money than the median family makes after tax in twenty years we know its bullshit. The inflation rate is papered over because of cheaper manufacturing due to technological progress and international trade, but it doesn't work for housing and many other things.

8. The more complex world is inherently less governable by democracies. A ballot only has a byte of information tops and it only operates over a period of four to six years. This is why lobbyists win, especially in larger democracies like America where the ratio of governed to lawmakers is higher.

9. Surveillance capitalism relies on inexplicable insights and returns. This hyper centralizes wealth whilst simultaneously shrouding the mechanism.

[0] Solving coordination problems is a form of governmental subsidization even if the government in question makes a huge profit. Canada does the same with forestry. I don't know how to square it with global trade.