diff --git a/mypy.ini b/mypy.ini
index b2afb32246..99d361208f 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -40,9 +40,6 @@ strict_optional = True
 
 # General exclusions to work on
 
-[mypy-zerver.views.registration]
-strict_optional = False
-
 [mypy-tools.lib.html_branches]
 strict_optional = False
 
diff --git a/zerver/views/registration.py b/zerver/views/registration.py
index b43db0c25b..56b366fca0 100644
--- a/zerver/views/registration.py
+++ b/zerver/views/registration.py
@@ -426,7 +426,7 @@ def accounts_register(request: HttpRequest) -> HttpResponse:
                  'require_ldap_password': require_ldap_password,
                  'password_auth_enabled': password_auth_enabled(realm),
                  'root_domain_available': is_root_domain_available(),
-                 'default_stream_groups': get_default_stream_groups(realm),
+                 'default_stream_groups': [] if realm is None else get_default_stream_groups(realm),
                  'accounts': get_accounts_for_email(email),
                  'MAX_REALM_NAME_LENGTH': str(Realm.MAX_REALM_NAME_LENGTH),
                  'MAX_NAME_LENGTH': str(UserProfile.MAX_NAME_LENGTH),