Episode Labels
Access protection is a separate setting
Labels and feed filters select the episodes in a feed. They do not limit access to specified people. The name "premium" does not make a feed private.
Confidential content needs a protected podcast with access control. Make sure that the access control works before you publish confidential content. Do not share personal feed links with access credentials in public.
The episode labels are used by the personalized feeds.
They are used as search filters. As an example, you can create 2 personalized feeds, a normal feed and a premium feed.
Whenever you add a new episode, you can choose to show it only in the premium feed.
This means you can add the "premium" tag to an episode and use it as a search filter in the premium feed.
See the protected podcast instructions for access protection and its limits.