King Salman has Alzheimer's and is largely a figurehead at this point. The rest of the world may shun MBS but he can rest assured that his good friend Donald Trump will still kiss his ass because Trump loves that Riyadh dosh.
On the bright side, even if MBS remains in power his ambition to create a strong well-educated Saudi middle class is likely going to create the institutions which will replace him
Yeah, Xi Jinping sure looks endangered by a growing Chinese educated middle class.

Nah, the Saudis will be fine with MBS in power as long as they get their movie theaters and Lexus SUVs.
IMHO, societies with a long history of autocracy don't automatically want to ditch autocracy just because they develop a bourgeois middle class. If anything, Western Europe was the aberration there. If the autocracy can provide them with all the creature comforts of a democracy, without any of the democratic mess, the vast majority of educated middle class people are going to be just fine with it.