The regime felt perfectly comfortable promoting this story because the moral was that revolutions, all revolutions, go badly, with the ordinary people suffering the most. The audiences however, took rather a different moral and were inspired by the heroic way the people were depicted. The opera was performed in 1828 by the Paris Opera and has been described as an "accessory before the fact" to the July Revolution of 1830 that ended the Restoration and made France a constitutional monarchy.
The runaway hit bestseller from the opera, disseminated in sheet music and barrel organ cylinders where it was heard everywhere on the street was a duet from Act II, "Amour sacree de la patrie" (Sacred love of fatherland). This was applauded with special fervor at every performance as a kind of anti-government demonstration.
When the opera was premiered in Belgium, then a protectorate of the Netherlands, in August of 1830, the authorities were especially concerned and cut out great portions of the opera, particularly scenes of mob violence. But they left in "Amour sacre de la patrie". It was so well-known by then that the whole audience was on their feet singing along. By the end of Act IV, most of the audience had left the theater and joined a growing crowd that occupied the offices of the newspaper, courthouse and Hotel de Ville, the main government offices. Then they stormed the municipal armory. In a few days the revolution had spread to the rest of Belgium and the Dutch withdrew. Within a few months, Prince Leopold of Saxe-Coburg-Gotha had been installed as king of the Belgians. His descendants still rule Belgium as sovereign monarchs to this day.
Now let's listen to that rabble-rousing duet from La Muete de Portici. For some reason, Blogger refuses to embed the link. Here is the URL on YouTube. The big tune starts at the 1:26 mark: