But given how clannish Arab society is, it just seems like a king would have enormously more legitimacy. In Jordan, love of the king is their patriotism.
Why does clannish imply monarchical legitimacy? Clans are kinship-groups, they don't have anything to do with states or monarchies. If anything, clannishness should mitigate
against the formation of stable monarchies, by functioning as an alternative location of sovereignty. Certainly there's no clear relationship between clannishness and the sort of popular monarchy you're identifying in Jordan, which seems to ask that people
set aside their identification with a kinship-group in favour of identification with a monarch.
The thinking here seems to be that clannish is pre-modern, kings are pre-modern, so the two must in some way support each other, but that's really just falling back on a flattened imagine of Ye Olden Days, the presumption that the past is an undifferentiated and unchanging whole, which isn't really true at all. "Traditional" social and political forms are as fluid and fractious as the modern, even if they played out over a longer time-scale.
It's also hard to draw the line between 'bourgeoisie and officialdom' and prestigious tribal members.
That's really just a function of kinship and patronage, isn't it? The old Marxist (really, Jacobin) dichotomy of aristocracy and bourgeoisie has never really held up in reality, was a matter of ideology even at the time, so I don't think it's some bizarre quirk of Arab society that a traditional elite and a modern capitalist class overlap heavily. It's just more obvious, is all, because the Peninsular Arab states have entered into capitalism with a peculiar combination of rapidity and autonomy which allowed traditional elites to transform themselves into a capitalist class while maintaining the trappings of a traditional elite. (And who knows how long that will continue to be possible?)
With the possible exception of the UAE, most Arab countries don't have a bourgeoisie that has any political power.
There's a difference between lacking political power and lacking
independent political power. They don't have a classical entrepreneurial bourgeoisie, that's true, but there is still a capitalist class in the Arab world, however dependent it tends to be on the state or on foreign capital. You might have to roll out the debated term "lumpenbourgeoisie" to capture the difference, but there's undoubtedly a capitalist social structure present, not just a state presiding over a mass of peasants.