Yes GDP is not the best metric but it does show a trend. That wealthier countries are developing slower that poorer countries.

It's not happening everywhere but most countries that don't have political problems are doing well.

There can be an argument that the rich west is guilty of causing some of those problems. For example Iraq is due to American interface. You could argue most of Africa is still suffering from the power structure left by the British.

But these are the results of past so s not the current system.

By dripping with intersectionalism I mean the author is dropping intersectional buzz words everywhere without making the case for why they apply. This is normally a sign that someone is simply applying an ideology to view a problem rather than any genuine analysis.