Apple Developer:
Later this summer, Apple will unify the email domains used by Sign
in with Apple and iCloud+ Hide My Email under a single, shared
domain:private.icloud.com.New addresses generated for both features will be issued on the
new domain. For example:
Sign in with Apple addresses, previously issued on
privaterelay.appleid.com, will be issued on
private.icloud.com.iCloud+ Hide My Email addresses, previously issued on
icloud.com, will be issued onprivate.icloud.com.Existing addresses on the legacy domains will continue to work and
forward mail to users without interruption.
Initial reaction to this change is that it might render “Hide My Email” ineffective, because shitbird services will simply ban the domain, trying to force you to use your primary email address. It seems inevitable that some number of services will do this. But my retort is that a service that won’t accept these email addresses is one that I probably don’t want to have anything to do with. The only reason not to accept private.icloud.com email addresses is if you want to do something invasive with users’ actual email addresses.
