Here’s the thing - Ramira is perhaps not being super-diplomatic in her arguments, but she has a point. Colibri, much more succinctly, does as well.
I’m going to carefully cherry-pick a quote here, but for a reason.
This is true. However what that has meant up until now is really very, very little. Here’s the wiki on the Egyptian Civil Code, which is worth a read. It also explains why I cherry-picked Egypt as an example. Egypt’s heavily French-influenced 1949 civil code is basically the backbone of a surprising proportion of the ME/NA legal codes. What this has meant in practive is that French secular law has had a rather more important practical influence on legal codes in the area than Islamic jurisprudence.
Note that the above amendment to the Egyptian constitution came in 1980, post-Nasser. And to date it has been used to do pretty much jack shit to alter the 1949 legal code as it stands. The concern about it is the potential to overturn secular laws, a real issue as the nation grapples with law in the post-2011 world.
But the OP was asking about what caused disparities, i.e. the history of why a shithole is a shithole. And the argument that the implementation of sharia is a good guide pretty much fails, because historically sharia hasn’t had much effective sway outside of a handful of countries ( and those, while grossly repressive of human rights in some respects especially the rights of women and minorities, also tend to be functioning civil societies with very low crime rates ). The rise of Islamism as a political force is very much a late 20th century phenomenom and doesn’t adequately describe why some countries suck.
Is Iran worse off because of the implementation of velayat e-faqih? Absolutely IMHO. But it was repressive as hell under the Shah as well, just in different ways.
Is Afghanistan a shithole because of the Taliban’s imposotion of their retrograde variety of sharia from 1996-2001? Hell no - Afghanistan was a shithole well before that.
Syria and Iraq, as Colibri so correctly pointed out, are shitholes created by explicitly secular regimes.
Basically this:
…is an interesting notion as a point of enquiry, don’t get me wrong. But in the end it doesn’t really pan out as a hypothesis. Because by and large sharia historically just hasn’t been that important or dominant in the region. It’s not that the map you cited is wrong, so much as it overstates the state of affairs and isn’t a historical overview. Honestly you’d be better off in a lot of cases blaming the widespread, half-assed and incredibly corrupt state socialism of the 1950’s-1970’s which didn’t due a tremendous amount of good to most of the regional economies.
The real answer to the OP is going to be different for every country and endlessly debateable. And personally I try to avoid endless debates these days ;).