ProtocolError occurred trying to complete the request. The server returned a status code of : Forbidden and the status description is : "Forbidden"
RSS feeds in SharePoint do not allow anonymous access. You will need to find how to send credentials with the request.
Do you use the RSS feed viewer web part?
If so, the RSS feed viewer web part does not support authenticated RSS feeds.
You could submit feedback via uservoice below. The product team will collect all your valuable opinions, and based on them, try making the product more user-friendly.
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