How did the estate system under the old regime contribute to unrest in France?

The third estate was treated unfairly under the old regime because they had to do all the labor, provide all the food, and were burdened with all the taxes of the French population. Also, when they complained of their oppression to the Estate's General (after Louis XVI called it back after 175 years) none of their suggested/ demanded reforms were passed, since they were outvoted by the first and second estates. The first and second estates were made up of the clergy and nobility, respectively, and they were happy with the way the government worked at the time, since they did not have to work or pay taxes. But they only made up about 3% of the population, and the third estate, the peasants, working class, and bourgeoisie (middle class) were 97% of France's population. Yet in the Estate's General, their influence was minimal since they only got one of three votes. Because of all this, the estate system contributed immensely to unrest in France, and later to the French Revolution