You can argue the growth of globalization & lowering of trade barriers were unrelated to this up-and-to-the-right, but it’s hard to argue they’re making things worse unless you really scope down to particular losers in a world of mostly winners.
I feel like those graphs and similar arguments are always trotted out, and they are an important piece, but there is more to the world than disposable income, and only using those stats completely ignores some very real negatives. You hint at it with "unless you really scope down to particular losers in a world of mostly winners", but I think you're vastly underestimating that:
1. Wealth inequality. Wealth inequality has exploded over the past few decades, and even if the median has gone up, the effects of widening wealth inequality can be very bad for society. First, as Charlie Munger once said, "The world is not driven by greed, but envy." Even if you're doing a little bit better, if everyone else is doing a ton better, this leads to you feeling like you're doing a lot worse. The rise of authoritarian politics in the West I think can be directly attributed by large swaths of society feeling left behind and like they are "getting screwed".
2. Related to the above, but finite resources, most especially land, are always vacuumed up by the wealthiest in society, regardless of any other level of incomes. So when there is a lot of wealth inequality, it can become prohibitively expensive to own land in any remotely desirable area, and this has huge negative societal effects (happy to go into this point more if you disagree).
3. The flip side of "optimized global supply chains" is incredibly brittle supply chains in the face of black swan events. Covid was a taste of this, though I think the global supply chain actually help up remarkably well for how enormous an impact Covid had. I think a better example would be something like chip production in Taiwan, which if it disappeared tomorrow would be absolutely devastating for the world economy.
4. Some countries that are now leaders in the world economy, like South Korea, had an extremely protectionist stance for decades in order to allow crucial industries to develop and not be undercut by cheap imports. I certainly don't think it's the only reason, but one reason Africa struggles so much is because they are flooded with cheap goods (or free goods in the guise of "charity") that prevent native industries from developing.
That first graph says the median income in 1974 was the equivalent of $5335 in today's dollars. I don't think it's adjusting for cost of living, because people lived a lot better in 1974 than you could live today on $5k per year.
But the political climate during that time period—starting on the left and now going to the right—has been that the middle class is being hollowed out. Is your argument that the Bush/Obama regime (recall that the Bush administration developed the bank bailout plan that Obama implemented) was basically correct? All the economy required was a little more regulation via Dodd Frank and the CFPB?
The argument that “the middle class is being hollowed out” is (IMO) pure dogma, there’s very little evidence to support it.
Take the median US household by gross income in 2003 & compare it to that same household in 2025. The 2025 household will utterly destroy it across any economic or hedonic metric.
If you control for household demographics and generational immigration history the gap becomes even more dramatic.
1. Wealth inequality. Wealth inequality has exploded over the past few decades, and even if the median has gone up, the effects of widening wealth inequality can be very bad for society. First, as Charlie Munger once said, "The world is not driven by greed, but envy." Even if you're doing a little bit better, if everyone else is doing a ton better, this leads to you feeling like you're doing a lot worse. The rise of authoritarian politics in the West I think can be directly attributed by large swaths of society feeling left behind and like they are "getting screwed".
2. Related to the above, but finite resources, most especially land, are always vacuumed up by the wealthiest in society, regardless of any other level of incomes. So when there is a lot of wealth inequality, it can become prohibitively expensive to own land in any remotely desirable area, and this has huge negative societal effects (happy to go into this point more if you disagree).
3. The flip side of "optimized global supply chains" is incredibly brittle supply chains in the face of black swan events. Covid was a taste of this, though I think the global supply chain actually help up remarkably well for how enormous an impact Covid had. I think a better example would be something like chip production in Taiwan, which if it disappeared tomorrow would be absolutely devastating for the world economy.
4. Some countries that are now leaders in the world economy, like South Korea, had an extremely protectionist stance for decades in order to allow crucial industries to develop and not be undercut by cheap imports. I certainly don't think it's the only reason, but one reason Africa struggles so much is because they are flooded with cheap goods (or free goods in the guise of "charity") that prevent native industries from developing.