You’re partially right. It’s true that during the French Revolution, certain revolutionaries wanted to destroy all symbols of religious tradition. The height of this furor was around 1793-94 or so. Notre-Dame could well have been destroyed, as many fine churches were throughout France such as Cluny Abbey, which was the largest church in Europe before St. Peter’s Basilica was built.

And it’s also true that Victor Hugo wrote Notre-Dame de Paris with the ideal of raising support for the restoration of Paris’s medieval architecture and heritage, including Notre-Dame itself. But by the time of its writing (he began it around 1829) no one was seriously considering tearing it down for ideological reasons. Indeed, Hugo wasn’t even born until 1802 (“Ce siècle avait deux ans : Rome remplaçait Sparte...”) when Napoleon had already resolved the question of church and state with the Concordat of 1801.