Comment by abdullahkhalids

Facebook for example has been shown in multiple public scandals and lawsuits to be untrustworthy. It is still among the largest social media platforms, and many businesses, for example, reveal large chunks of their marketing strategies to Facebook through its advertising tools.

The reason why this does not result in a significant loss of usage is because trustworthiness-usage is not a linear function or a even a continuous function -- it is a step function. To cause less usage, the loss-of-trust force has to be higher than the networking effect force. Otherwise, behavior does not change.