New site setting to hide user profiles by default

Continuing the discussion from 2.9.0.beta12: Security fix, bug fixes and more:

Thanks. Could you provide more information about that feature ?

이것은 사용자의 프로필/인터페이스 페이지에서 "공개 프로필 및 존재 상태 기능 숨기기"를 기본적으로 활성화(즉, 기본적으로 프로필과 존재 상태를 숨김)하도록 설정하는 새로운 default hide profile and presence 관리자 설정입니다.

이것은 이 Contribute > Feature 토픽에서 제안되었습니다 - Opt-in to show user profile instead of opt-out

Could you elaborate a bit on the meaning of “public” in this context?

Who can see the user profile if the user has not opted in?

Is there a way to show profiles only for members of shared groups or more restrictively, for shared groups that require approval?

I have explained my reasons for requests like this here:

I’m afraid it doesn’t change the behaviour of the setting in any way, only what is marked as the default.

If a user has ‘Hide my public profile and presence features’ enabled it will hide their profile and ‘x is typing’ indicator from anon and all non-staff users.

There are a couple of connected admin settings that also have an effect - allow users to hide profile and hide user profiles from public (which disables user information features for anon), but neither would limit avatar visibility.