I can find no other sources claiming a Dutch Gini coefficient higher than 0.3 at any point in recent history. A Gini coefficient of 0.902 is practically unheard of, perhaps the article was written in error? Seems strange to put so much effort into writing an article without checking the source or questioning the number.
By comparison, Russia's Gini coefficient is 0.375 with the noted caveat that it can be very hard to track the true wealth of the most powerful Russians. The United States is 0.414 according to same source.