Who and why was dissatisfied with Spanish rule in the Netherlands?

First, the Protestants were unhappy. The Spanish administration planted Catholicism in the Dutch provinces (Holland, Zealand, etc.), infringed on the rights of the Protestant population and pastors, and interfered with freedom of religion. Secondly, the Dutch aristocracy was unhappy. To her opinion on the solution of the main problems of the Netherlands was little heeded, everything was led by the Spanish governors. Third, the Spaniards had a very rigid and extortionate tax policy in the Netherlands.