The technology sector only represents 9% of US GDP, biotech less than 1.5% , aerospace less than 2% . In total, software/IT, biotech, aerospace constitutes less than 13% of US GDP, so you are wrong that is why US GDP per capita is high for a sectors that is not representative of broader US economy.This is where you are wrong. I also discussed this in another thread recently. This notion that world cannot sustain US and China having the same GDP per capita is based on a flawed assumption that GDP per capita can only go up. It can also come down.
The main reason behind US high GDP per capita is its high tech dominance. Its dominant in industries such as software, internet services, biotech, aerospace. This is the basis of the all the high salaried engineer jobs in the US. Without those jobs, what will happen to US GDP per capita? It will crash down.
China is developing its industry in all of these sectors. Every sector where the west is dominant is under threat of current or future Chinese competion. Once China replaces western products and software in its own borders, it will start exporting these to the outside world.
With Chinese lower cost of living and hard working 996 culture, its inevitable that they will take away market share from the US and western countries in all those high tech fields. Once that happens, Chinese GDP per capita will go up and US GDP per capita will go down, therefore closing the gap.
You have another flawed assumption about world's resources. Resources in this world maybe fixed, but there is no rule that only the US can buy those resources. As China gets richer, it will bid higher and higher prices for those resources. US will be forced to consume less and less and China will be taking away more of the resource share. In the end, we will have resource consumption equality between US and China.
There is no guarantee that 80K dollars will buy the same amount of resources and comfort in the future that it does now. The more China and other developing countries develop, they will demand those same resources and the prices of those resources will rise significantly. This will cause aj reduction in standard of living in rich countries like US and Europe.
The key to prosperity and comfortable living is money, and the key to money is strong industrial power. China is gaining both. Moreover, the world is moving from resource consumption inequality to equality. This will have catastrophic effect on US standard of living in the future.
In contrast, private consumption as defined by private spending on goods/services/equipment constitute 70% of the US GDP .
So 13% vs 70% of GDP, the numbers don't lie. There is no way 1.4 billion Chinese can emulate the wasteful private consumption habits of US consumers. It's literally unsustainable from a CO2 emissions perspective.