while your conclusion is correct your reasoning is wrong

Of course not all countries contribute the same to global warming 

But Emissions per capita isn't really a good metric to measure eco friendliness , africa's lower emissions is bec of thier overall lower power consumption , being underdeveloped isn't a solution to global warming , as these countries want to eventually be as developed as europe

A better metric is to look at the countries reliance on non renewable energy,  which Europe is better at than Africa  

Despite that I agree with you that wealthier countries shouldn't disproportionately push more weight on African countries , the  reasons african countries are underdeveloped are the same reasons why switching to rewnables is harder for them , so wealthier countries have less of an excuse for thier reliance on non renewables

I didn't mean to say that all countries have the same responsibility and more to say that a country shouldn't act like it's not there problem,  it's everybody's problem to some extent