Hmm, FullStory would be hard to use for evil. It's used to creators can track down issues and bugs and provide better customer support, not to do anything malicious.

You can still argue you don't want your data sent to them, and that's very fair, but the only way this helps their business model is if their business model is "provide really good, tailored customer support."

Puh, not sure if that brings you the sweet, sweet investor money and some data leaks in the long tail. You should really go all in on data collection. Always!