It's still possible to access r/all, even if the app won't let you.
"As part of ongoing efforts to simplify Reddit and improve Home feed personalization, the final steps to deprecate r/all are ...
Reddit is now going to redirect you away from r/all, though you can still find it by loading up old Reddit.
Reddit has officially shut down r/all, its unfiltered discovery feed, redirecting users to the personalized Home feed or ...
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