I don't have the answers but consumption reductions during COVID might provide a useful yardstick. Global CO2 emissions decreased by 17 percent compared to peak 2019 levels. What can't survive a reduction in consumption is our economy. GDP is the holy grail by which all economic decisions are made.

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https://www.nature.com/articles/s41558-020-0797-x#:~:text=Daily%20global%20CO2%20emissions%20decreased%20by%20%E2%80%9317%25%20(%E2%80%93,by%20%E2%80%9326%25%20on%20average.