And they apparently transition to an average of 0-2 children naturally as a function of wealth management and survival confidence.

1. Not really, the richest x% own and run the companies, and can spend more, but the mass of consumers of the products are spread across the wealth spectrum.

2. The idea to reduce the population based on some metric is a dangerous road to go down on.

3. By definition there will always be a richest 10% regardless of how many humans you get rid of.

> almost all emissions are caused by the richest 10%

I found this: https://ourworldindata.org/co2-by-income-region but it does not talk about individuals, only countries and regions; it finds that "the richest half (high and upper-middle income countries) emit 86 percent of global CO2 emissions". According to the graph, 16% of world population in high-income countries are responsible for 38% of global CO2. The richer 51 of the world population cause 86%. I don't think this squares with your statement, even if both "almost all" and "10%" were hyperbole.