Apple has disabled SharePlay in the latest operating system betas and announced it wouldn't be arriving at launch in the fall.
SharePlay was enabled for testers starting in iOS 15 developer beta 2. Those who update to developer beta 6 or later will not have SharePlay again until after the fall launch.
The release notes read as follows:
SharePlay has been disabled for use in iOS and iPadOS 15 developer beta 6 and will be disabled for use in its initial release this fall. SharePlay will be enabled for use again in future developer beta releases and will launch to the public in software updates later this fall. To continue your development, we have provided a SharePlay Development Profile which will enable successful creation and reception of GroupSessions via the Group Activities API.
SharePlay is a feature that allows users to share media during FaceTime calls. Users can watch movies, listen to music, or see someone's screen with all callers in perfect sync while using SharePlay.
Apple did not provide any reason for the feature delay. Issues could range from technical to legal when dealing with sharing media.