What are the criticism of freemium?

Could you elaborate on the criticisms surrounding the freemium model? Some argue that it can be manipulative, encouraging users to upgrade to premium features through psychological tactics like limited access or functionality. Others criticize the lack of transparency in pricing structures, leading to unexpected costs for users. Additionally, there are concerns about data privacy and the potential for the model to be abused by unscrupulous companies. How do you respond to these criticisms?