I tried that and I would tend to agree with you that in principle a sequential color map would be the preferrable choice. However the big advantage that a diverging scale gives, is that the extremes in either direction are highlighted which I think gives more immediate insight for this kind of data. You can immediately see which countries have not reduced their emission yet, but also which countries have reduced their emission a lot.

With a sequential map only one of the extremes would stand out.

I do not know what is up with North Korea, but apparently their carbon output is reducing. If that is because of a shrinking economy or measures taken especially to reduce their emission I can not tell.

You can dig in to the data sources yourself here: https://github.com/owid/co2-data

Countries with recent conflict and unrest (e.g. Syria, Venezuela, Yemen, Somalia) stand out with involunatrily reduced carbon emissions.

Also note that the most recent data is from 2020. So the great reduction of CO2 emissions in Ukraine can not be attributed to the invasion.

But the data is recent enought that the Covid pandemic has an impact on the visualization, with many countries increasing their emissions again in 2021.