LAN hasn’t been changed and we use it all the time. This message originates from the connection server, which is not involved at all if you properly set up a local connection:
a) do not log in on either end
b) have both Cubase/Nuendo and Performer computers connected to the local network (router) and VST Connect plugin active
c) The LAN button within the Performer application (looks like a WiFi icon) should be lit blue. Click to select the other side and it will connect.