the sharing system used for this video implies that some technical information about your system (such as a public IP address) can be sent to other peers.
Web peers are not publicly accessible: because we use the websocket transport, the protocol is different from classic BitTorrent tracker. When you are in a web browser, you send a signal containing your IP address to the tracker that will randomly choose other peers to forward the information to. See <x id="START_LINK" ctype="x-a" equiv-text="<a href="https://github.com/yciabaud/webtorrent/blob/beps/bep_webrtc.rst">"/>this document<x id="CLOSE_LINK" ctype="x-a" equiv-text="</a> "/> for more information
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.
The threats to privacy with YouTube are different from PeerTube's. In YouTube's case, the platform gathers a huge amount of your personal information (not only your IP) to analyze them and track you. Moreover, YouTube is owned by Google/Alphabet, a company that tracks you across many websites (via AdSense or Google Analytics).
