The worst-case scenario of an average person spying on their friends is quite unlikely. There are much more effective ways to get that kind of information.
PeerTube wants to deliver the best countermeasures possible, to give you more choice and render attacks less likely. Here is what we put in place so far:
An HTTP request has to be sent on each tracker for each video to spy. If we want to spy all PeerTube's videos, we have to send as many requests as there are videos (so potentially a lot)