Sorry, I find that statement quite imprecise: you could connect to a single server at a time, just like a browser tab connects you to only one service at a time

Sorry, I find that statement quite imprecise: you could connect to a single server at a time, just like a browser tab connects you to only one service at a time (even if it uses many libraries from many other http servers), so if you mean peer to peer this way, then yes. But then to do that, it connected to a massive infrastructure that was there and running with very high availability constraints, ... for the time ;-)