Totalitarianism does have some benefits.
One advantage of democracy is that there is a mechanism for peaceful transition of power if the current leadership isn't working. Without this, a country has to resort to armed rebellion.
China has historically legitimized armed popular rebellion with the concept of the "mandate of heaven". When an armed popular rebellion topples a dynasty, the previous dynasty is said to have lost its mandate of heaven and the successful rebel leader is said to have gained it. This is why China has historically had dynastic cycles. Democracy is a possible solution for escaping the cycle of often disastrous and very bloody armed rebellions.
I would go so far as to say that the peaceful transition of power is the defining advantage of democracy.
1. High standards of living that alter the risk-reward ratio for making a political change
2. The rise of Corporations - these days, people view the government as a bureaucratic, slow, and useless entity with decent, but low pay. People aspire to work and move up the ranks in private corporations. The role of the government has been greatly reduced in the ordinary lives of citizens. That means the necessity of making a grand political change is just not as important as it was historically.