Support Hub provides the article RSS feed for each account.
The feed with all published articles that can be publically visible is available on https://yoursubdomain.support-hub.io/feed
If you want, there is a feed available for each category separately, and you can get the URL to the feed at the bottom of the category collections page like it is displayed on the screenshot below:
For example, here is the URL to the General category here on the official Support Hub help desk: https://help.support-hub.io/feed/3