Multiplayer doesn't need internet. Neither the client nor the server does. I think the parent made a mental jump here: the problem is when multiplayer needs a

Multiplayer doesn't need internet. Neither the client nor the server does. I think the parent made a mental jump here: the problem is when multiplayer needs a particular endpoint on the internet, and when that endpoint is unreachable (firewall, bad connection, product discontinued), then multiplayer is broken.