There’s no way of knowing, which is the whole problem with their model and why a lot of us self host things in the first place. Even if they super duper promise not to use the data, they could be lying. And if they are actually true to their word today, that could change tomorrow.
I just tried subscribing to !sircmpwn@spacepub.space, but it’s empty despite the peer tube channel having many videos. Any idea what’s going on?