It's still possible to access r/all, even if the app won't let you.

Reddit is now going to redirect you away from r/all, though you can still find it by loading up old Reddit.

"As part of ongoing efforts to simplify Reddit and improve Home feed personalization, the final steps to deprecate r/all are ...

Under new rules rolling out over the coming months, a small number of users will be required to leave some of their moderator posts so that they aren’t moderating more than five subreddits with ...

In update notes published Thursday, Reddit said that the “the final steps to deprecate r/all are being implemented,” and links to r/all now redirect to your Home feed. r/all also doesn’t show up on ...