While a common-enough failure mode, this is by no means universal. Many successful monarchies began as the equivalent of dictatorships, and then opened up further and further over time.

And then there's the Roman Empire, which started as a dictatorship (in the literal sense to which all other uses are metaphorical allusions) and went the other direction.

Spain for example wasn't a democracy until the 20th century and the first attempt at democracy failed miserably and only the second succeeded after the monarchy backed dictator died and the king didn't follow the late dictator's legacy as planned.

https://en.wikipedia.org/wiki/English_Civil_War ended with the execution of the Monarch, a brief military dictatorship, and established the principle that the Monarch cannot rule without the consent of Parliament.

Not exactly the French revolution, but hardly a smooth transition either.

Louis the 14th of France was one of the first Western kings to have something like dictatorial control of a country rather than being quite dependent on the nobles formally under him (as those nobles were in turn dependent on their vassals).

You've both made a good point and refuted the absolutist position at the same time. In general, if monarchs change and the borders, the laws, and the identities of the people remain the same, then it's really a continuation of the same regime. Really, "it depends."