What are the main reasons for the popular dissatisfaction that stood out in the uprising? Under Catherine II the Great?

We are talking about the Pugachev uprising in 1773-1775, it became the largest during the reign of Catherine II, the rest were smaller in scale.

The reasons were as follows:

The loss of their privileges by the Yaik Cossacks, this process began in the era of Peter I. For example, the Cossacks were transferred from the subordination of the Collegium of Foreign Affairs to the subordination of the Military Collegium.
From this followed the elimination of the election of the military chieftain. The Cossacks could not replace what they disliked.
The split of the Yaik Cossacks from the 1730s into military and petty officers.
Monopoly on salt since 1754. Cossacks traded in fish and caviar.
The refusal of the Cossacks to poison the team to strengthen the Tver line.
The Cossacks refused to submit in pursuit of the Kalmyks who had migrated from Russia.
Dissatisfaction of the assigned peasants, these were state peasants who were assigned to the Ural factories.
Strengthening serfdom.
Peter III freed the nobles from compulsory service, and for some this gave rise to false ideas about the liberation of the peasants, so the people followed the impostor.