The accurate bit is that Gulf states are teeming with immigrants but they are incredibly stingy when it comes to giving out citizenship. There are strict racial, tribal, and nationalistic hierarchies; some written but many unwritten, that influence how you are treated in these countries.
In Bahrain, however, these same types of expats have a lot more freedom and their rights are better protected. They can move around more easily; I think they can leave the country without their sponsor's approval; and they also can switch jobs much more easily.
I think the situation in Qatar is closer to Bahrain than Saudi Arabia, but I've never actually been to Qatar except to the airport in Doha.
PPP is useful when looking at, for example, average wages amongst entry-level employees, or... um... it's a short list. It has its uses. It just gets overused a lot. The worst overuse of it is trying to measure total GDP. Per capita income is somewhere in the middle.
Bahrain used up its oil reserves quite a while ago. The country now has a Russian vagina based economy. There are quite a few lower-class neighborhoods around the small island and even in Manama. They are not as wealthy as their Gulf neighbors. But not quite poor, either.
Is that a typo? Or do I not understand the reference.
I doubt that.
Now this does not clear the whole truth.
The others before her are either harbours for moneymovers, with an oversized financial sector, or clan-based countries totally dependent on petroleum revenue. Ireland is, unfortunately, in the first category.