I'm not sure why you're bringing up the Peace of Westphalia when the topic is how monarchies transformed into democracies. There weren't many democracies at that time.

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.

Uh,ok, if you're going to be intellectually dishonest and move the goalposts "here is the single path that dictatorships take (demonstrably not the case in whatever the final dictatorship that transitioned to democracy for each given non-revolutionary countries)...Spain, Portugal, and Chile were all examples from the last half century. How do both this and the general case I described _not_ refute your point?