It's essentially a map of big countries (population, territory, population density...)
This map would be way more interesting if it was normalized per capita or some other meaningful denominator. Only then does it make sense to point fingers.
A few of the dimwits I work with use china alot as a reason to not do anything about climate change because they keep building coal plants but... The coal plants they build are more efficient.
According to this chart the UK is doing well but we can still do better and we should keep doing more.
It's about future oil and gas expansion (FOGE), what matters to the atmosphere is the total - identifying potential threat.
Effectively multiplying FOGE by area (as shown) doesn't make sense, but neither does FOGE per capita (as most is exported, not consumed locally). I'd suggest just a sized blob for each country - then can show some other dimension with the color.