So there's something interesting about Elden Ring right now and it's match making. There's an item called the taunters tongue that gives 100% priority to said host of a world in the eyes of the match making. If this player blocks you the game will keep trying to connect to them regardless of the connection being blocked by the host at that point. So in theory, if someone was to spam this item in every invasion area of the game across a few clients of the game and had some auto block scripting going on they could effectively shutdown invasions as a whole.