PeerTube initially aims precisely at being a Youtube alternative, which is why such questions are not tackled in the article I guess. However federation with other servers is totally controlled by admin-defined rules, so you can make a “private” instance. I'm not sure whether making videos watchable by logged-in users only is already possible but it's a very easy thing to implement.

As for the torrenting, if videos are only available to members it shouldn't be a privacy problem. That being said, disabling it will probably be a possibility in v1.0.