Pretty sure is historical emissions data. China and India have like 20 years of emissions, that are still pretty low when accounting by per capita or by "imported emissions"*, while United States and Europe have been producing carbon emissions for more that a century now.
* imported emissions are emissions caused by industry that is going to export the products to be consumed elsewhere.
The top 10 most polluting countries according to the IPCC:
Qatar — 37.05 per capita
Kuwait — 23.49 per capita
Saudi Arabia — 19.39 per capita
Canada — 16.85 per capita
United States — 15.74 per capita
Germany — 9.7 per capita
China — 7.72 per capita
Spain — 6.09 per capita
France — 5.02 per capita
Thailand — 4.05 per capita
Greenhouse gas emissions by China are the largest of any country in the world both in production and consumption terms, and stem mainly from coal burning in China, including coal-fired power stations, coal mining,[3] and blast furnaces producing iron and steel.[4] When measuring production-based emissions, China emitted over 14 gigatonnes (Gt) CO2eq of greenhouse gases in 2019,[5] 27% of the world total.[6][7] When measuring in consumption-based terms, which adds emissions associated with imported goods and extracts those associated with exported goods, China accounts for 13 gigatonnes (Gt) or 25% of global emissions.[8]
The source of the map says "National Cumulative", this why I said I think it means historical emissions and not emissions of today. Also, a more just way to measure it would be for consumption, not emissions, a lot of the emissions generated on china is generated on the manufacturing of consumers goods to be used on the first world.
Per person, emissions in both China and India are still substantially lower than almost all developed countries. India’s per person emissions are less than one-quarter of the global average, and roughly one-tenth of those of the US. Close to a quarter of all carbon emissions come from manufacturing products which are exported and consumed in other countries. Textiles and clothes exported from India and south Asia account for over 4% of global emissions.
Labelling India and China as the chief villains of COP26 is a convenient narrative. The financial aid which rich countries promised yet failed to deliver as part of the Paris Agreement signed in 2015 was supposed to help developing countries dump coal for cleaner sources of energy. And while the world berated India and China for weakening the Glasgow Climate Pact’s coal resolution, few questioned the fossil fuel projects being floated in developed nations, like the UK’s Cambo oilfield and the Line 3 oil pipeline between Canada and the US.
And that's without even going back to look at imperialism and its impacts on those countries, and why they're now having to play catch up with the west (who not only did our fair share of polluting during our own industrial revolutions, but still continue to do so pretty much freely), mostly to provide for the west.
This, like the overpopulation myth, are nothing more than racist distractions created by the rich and powerful to get us to blame "others" rather than look for who is really at fault - them (Edit to clarify: and by them I mean all obscenely rich and the governments they control, faux communists included).