Apple Arcade is a distinct platform from iOS app store, and they have special requirements in order to have a multiplayer feature in the app. We were unaware of this and accidentally turned on multiplayer for a short time, but had to revert it. Since multiplayer on mobile is an experimental beta feature, our priority right now is to fix and support the "standard" features in the mobile apps. But we will investigate the possibility of getting multiplayer on Apple Arcade in the future.