Do not hide all the elements of the units with problems to anonymous users:

Right now the units of a public course are hidden if there is at least a graded activity in them. This is done due to a change(69eeca61d8) that was done before the implementation of public_view mechanism for unenrolled users.

Since we use public_view now and by default it restricts the unit rendering for anonymous users we do not need to limit the access at this way for anonymous users.

common/lib/xmodule/xmodule/seq_module.py

@@ -520,13 +520,6 @@ class SequenceModule(SequenceFields, ProctoringFields, XModule):
             item_type = item.get_icon_class()
             usage_id = item.scope_ids.usage_id
 
-            if item_type == 'problem' and not is_user_authenticated:
-                log.info(
-                    'Problem [%s] was not rendered because anonymous access is not allowed for graded content',
-                    usage_id
-                )
-                continue
-
             show_bookmark_button = False
             is_bookmarked = False