Monarchy is the solution to multiple problems that I feel have historically faced fascist/Third Positionist countries.

1. Concretes succession- Rather than passing on leadership to seemingly random ministers or other officials such as in the Third Reich, or causing a weakpoint or crisis that can be exploited by natural decay/uncertainty or by hostile actors, the monarch has one or more suitable heirs literally trained from birth to exist for the sole purpose of serving and leading the people the best he possibly can.

2. Creates a somewhat apolitical figurehead and personification of the country- Historically, monarchs and other important people were seen not just as petty politicians but as representatives and personifications of the country and people/society of that country. They were also a uniting figurehead, wherein everyone that liked or agreed with the monarch has a common ground and a common enemy- those that do not.

2.5. Creates a personification of the government- Sort of related to the previous point, the monarch also provides a figurehead for the state. Rather than being a nebulous and expansive entity that nobody can relate to, the monarch creates a personal connection for the people to the state, and can issue judgements and opinions on behalf of the state that have a greater effect. For example, if a certain company decides to defy the government, a nebulous and octopus-esque state issuing a formal statement only carries a certain amount of weight with the people and with the company. However, a monarch, a person in the flesh of high esteem, issuing a scathing opinion or judgement upon a company would not only hurt that company outright but also turn the people against that company and/or the actions it took to warrant that censure.

1. Successors are already trained and guaranteed to be more or less ideologically loyal- The monarch either directly trains his heirs or indirectly influences them, be they not in his family, so a stooge in office is a far less likely occurrence than it is in a democratic system. This is amplified if an elective system with a regulatory council that assists, elects, and regulates the monarch exists, as they can remove bad heirs/monarchs, and help pick the best leaders in the first place.

2. Monarchy embodies lots of our values- The monarch embodies and protects the sovereignty, the traditions and culture, and other important factors of the nation that we fascists/Third Positionists put lots of value in.

I could make other points but these seem to me to be the biggest and most important.