Well for the in depth take on all this I'll direct you to Mike Duncan...
But my understanding of all this was that the French were taken by the ideas of the philosophes, Montesquieu built on the ideas of Locke, and Rousseau was a counterpoint to the dry philosophes, proposing romantic and more radical anti-establishment ideals. These were all freely discussed in the tea houses of the day.
Expectations were amped up in proposing representation of the third estate and reducing the power and influence of the clergy and nobility... but the king and his ministers would repeatedly clumsily back away from these promises at the last second only to give in completely under pressure of the mob when frustrations exploded among the urbanites or the peasants... ultimately the military refused to enforce orders and the king was rendered powerless.