Doesn't most of that apply to the justifications for the One Party System and the whole Supreme Leader thing too? Like the rebuttals of and proponents for Imperial rule isn't exactly new or rare or anything close to never been tried.
There is a massive difference between traditional and absulte monarchy, though, as well as between any kind of monarchy and a one party system.
In a traditional monarchy, you don't need much more than a monarch because most of the governance is carried out at local and regional level. As such, bureaucracy is very small (and usually, rather efficient), and people have major - if often extralegal - influence on politics and policies because decisions are made at very low level, where decision-makers are within arm's reach. Oftentimes, literally so - and they know it. For example, much is made today of corruption at local level. But this does not mean that local governments are more corrupt than central one - rather, they
appear more corrupt because corruption is easier to notice, and in any case much of corruption in central government is given legal veneer.
In an absolute monarchy, state is literally personal property of the monarch. Monarch makes basically all decisions and bureocracy then implements them - in theory. In practice, monarch makes many decisions but many are also made by various interest groups. Difference, then, with traditional monarchy, is that absolute monarchy has a massive bureaucracy which allows utter centralization of the decision-making. This means that any bad decisions impact everyone, and are often long-lasting. Yet the fact that the state is property of a monarch means that monarch at least has personal interest in ensuring that state prospers. As a result, much depends on the personal competence of the monarch as well as his ethics and emotional maturity.
One party system is by far the worst because it has all disadvantages of an absolute monarchy combined with all disadvantages of a democracy, and advantages of neither. Much like absolute monarchy, it is difficult to impossible to get input of the people, much less to make government listen to it. Administrative apparatus is all-pervasive and enters all the pores of the society, yet it serves only interests of the central government. And central government often means a single person around whom the party has coalesced (e.g. Stalin, Tito), and said person tends to be emotionally immature, unable to recognize their own limitations yet drunk on worship. Much like democracy, one-party state has a massive and inert political system which is often focused inwards, caring more about internal competition and power struggles than about whatever problems are facing the society - yet unlike democracy, it has absolutely no need to care about the electorate, nor to even pretend to care. It has literally nothing good: neither the small central government of a traditional monarchy, nor the need to at least fake caring about popular opinion that democracy has. Thus it is free to bury its head in the sand, turn inwards and fossilize. There is also no sense that the state is a private property, which at least somewhat pushed absolute monarchs to care about it: in one-party systems, state is the property of the
party, everybody is responsible for it - which in practice means that nobody is responsible for it, state is merely a money cow which members of the party milk until it collapses.
Modern civil democracy is also bad, because civic nationalism basically denies the state as a property of a certain group - it is the property of whoever happens to come live in it, with no obligations. Thus people have no incentive to protect it, yet every incentive to milk it until it dries up.