Nitpick, but MBS isn't the sovereign. His father is.
Given MBS isn't acting as regent, he's actually--in the most technical way--a tyrant: "the tyrant was Very Obviously but not formally in charge, because he ruled extra-constitutonally, rather than abolishing the constitution. This is what seperates tyranny, a form of extra-constitutional one man rule, from monarchy, a form of traditional and thus constitutional one-man rule" [1].
[1] https://acoup.blog/2023/03/17/collections-how-to-polis-part-...
His power is not (as far as anyone not privy to the private preferences of King Salman can say) extraconstitutional, since it flows directly from royal decree giving him the position and authority he holds, and Saudi Arabia is an absolute monarchy where any delegation of authority the King makes is, ipso facto, constitutional.
Do you have a source for the decree? (EDIT: Nvm, Salman delegated various affairs to MBS [1], as well as made him PM [2]. Salman remains the head of state.)
I'd still argue that MBS is not formally in charge. The President can delegate their authority to a rando, that doesn't make it lower-case constitutional, e.g. Edith Wilson [3]. (Granted, that was done without formal decree.)
Going back to the Greek analog, tyrants would usually gain some instrument from the formal leader technically legitimising their actions. But the formal leader wasn't the one deciding. The tyrant was.
[1] https://www.reuters.com/article/idUSKBN1DA23M/
[2] https://amwaj.media/media-monitor/saudi-power-transition-con...
[3] https://en.wikipedia.org/wiki/Edith_Wilson#Increased_role_af...
Monarchy is telling you "who" has the power, and tyranny is telling you "how" the power is used.
Not even mentioning the existence of constitutional monarchy. It's the political system of many countries, including Norway and Sweden.
So, in order to really convey useful information, one would have to use different words, such as "democracy" (which can be "liberal", or the extreme opposite "illiberal"), "dictatorship", etc.
MBS isn't acting as a regent, though. Salman remains the formal head of state.
Dragonwriter made a compelling point, however, in Salman having formally delegated a lot of powers to MBS. So maybe MBS isn't a tyrant, though it's difficult to argue either Salman or MBS are absolute monarchs at this time in practice. (Their "crown" retains absolute power. But that's slightly, and very meaningfully, different.)
Its not the monarch's design, its the prime minister’s (the PM is also the heir; which is also a break from earlier tradition, as previously the monarch was also PM.)
Though at the time of the design, MBS wasn't PM, the King was still PM, and MBS was Crown Prince (as he remains) and First Deputy Prime Minister and Minister of Defense.
