They could explain how they use data from their users "to improve our models". In the absence of that, how can we make informed decisions about how to use thei

They could explain how they use data from their users "to improve our models". In the absence of that, how can we make informed decisions about how to use their tools? (And "you can opt out" is a weak answer IMO, because I can't guarantee that everyone I email about something has also opted out.)