I figured you would come back with that. As Adam Smith pointed out, "there's a lot of ruin in a nation." It takes a long time to wreck one, but drugs in China managed to do that in ~70 years. A Four thousand year old form of government collapses 70 years after drugs wrecked their economy and their society.
But see, you were arguing that the revolution was the result of a lack in faith for their government as a result of their defeat by the British. It's easy to see why a collapse in economic and social activity might take seventy years, but it is not at all easy to see why political anger would take so long.
But you know what? I recognize that you aren't trying to illuminate anything. To the contrary, you are trying your very best to steer people away from reasonable understanding in an effort to save your "Idee Fixe".
You are a deceiver.
Really - in a pre-mass communication age and a vast country, a monarchy taking 50 years to feel the effects of political anger is not at all easy to see?
Talk about an effort to save your "Idee Fixe".