Their email and even their “Plex: Free vs Paid” page is confusing. However, the “Requirements for Remote Playback of Personal Media“ is more clear.

I do not have a Plex Pass, but I stream remotely from a Plex Media Server

To stream video remotely from a Plex Media Server, you will need either a Remote Watch Pass or Plex Pass subscription on your account or the admin of the Plex Media Server from which you stream will need a Plex Pass subscription on their account.

You can self-host Feedbin or you can get a paid account for $30 USD.

Lots of great functionality built-in. I use Unread app for iOS as the front-end instead of Feedbin’s web app. A paid Unread account would also give you RSS feed hosting, but less feature rich.