From Three wild speculations from amateur quantitative macrohistory but there is nothing wild about the diagram other than how ignorant most people are about what it shows.
In How big a deal was the Industrial Revolution?, I looked for measures (or proxy measures) of human well-being / empowerment for which we have “decent” scholarly estimates of the global average going back thousands of years. For reasons elaborated at some length in the full report, I ended up going with:
Physical health, as measured by life expectancy at birth.
Economic well-being, as measured by GDP per capita (PPP) and percent of people living in extreme poverty.
Energy capture, in kilocalories per person per day.
Technological empowerment, as measured by war-making capacity.
Political freedom to live the kind of life one wants to live, as measured by percent of people living in a democracy.
Two million years of “human” history where the only tools were made of stone, and then a bronze age, iron age, industrial revolution and now us.
We now have morons [who call themselves “progressives”!] trying to take us back in time to just where I don’t know, perhaps 1890, maybe 1920, but certainly to a time of greater poverty and fewer chances in life. The diagram is only for us because most of those trying to kill off our carbon-based energy sources would be too thick to understand any of it since the basis for their entire ideological view of the world is a hatred for the capitalist system that has transformed the human race.