Political Bakunin would argue that the state that assumes the consent of the people is coercive because Bakunin did not accept the premise upon which much of Western political theory was launched. He was totally against the social contract theory so familiar to the West in the writings of Enlightenment thinkers, especially J. J. Rousseau. Bakunin didn't believe in any consent other than direct consent.
Tacit consent is considered reasonable political theory for several reasons.
Imagine if every citizen in every country was asked to consent to be governed by one government. This idea is ludicrous. Such harmony is abhorrent to human nature. But there are viable options for those who wish to withdraw their consent to be governed. Bakunin, for example, engaged in riots and distributed illegal literature to spread his ideas.