The army generals in Myanmar know how its done. Now South Korea is getting into it. The dimissed president has called in the army to protect him against a court order and arrest by police. In effect this is a new martial law dictatorship.  In a shoot out between judges and troops, the odds are not good.  So both north and south Korea are under the hammer. It's all very quick, tidy and suits elderly orange presidents.

There was a possibility that Whitlam may have disputed his dismissal in 1975. Then the PM and Gov Gen as the two authorities may have called on military backing which could have been a divisive tragedy. The rare situation is equally possible in a republic but a monarchy at least has some more depth and vibes for continuity.

Arrr, aye - retain trappings of Overlordship by force and vestiges of now old and worn-out Feudal system where King can impose at will.....  arrrr-aye ... touch forelocks and say 'Aye'!  or it's Dismissal for you and worse!

Make sure the Old Guard never lose control over the peasantry - damn - that would startle the horses....   ;D  ;D  ;D  ;D  ;D

For the umpteenth time - you can organise a Republic any way you want.... you don't need to be bound to the failings of past similar government styles.

Any system needs one person as organiser. The name or definition is irrelevant.  Communist Sec General, Holy Father, El Supremo, Peter Dutton, all the same.  If he goes feral and the others don't, it's bad news.