And then they overthrew that monarchy, had a second republic for four years, Napoleon III declared himself emperor, the empire collapsed, and they had a third republic, which was overthrown by the Nazis, and then a fourth republic after the Nazis lost, which only lasted another twelve years before they changed enough laws to call it #5.
Boy, I bet they would have preferred to skip ahead to overthrowing the monarchs indefinitely.
And how the absolute fuck do you propose they could have reformed a monarchy that responded to protests with violence? Even the French don't overthrow their government without giving it a chance to respond to their demands.
It's like suggesting that a union get concessions without striking. Sure, they'd like to, but if the company refuses to negotiate, there's only one (legal) path forward.