Feeed[0] nailed the ux for a rss reader (and other type of feeds) by having a local algorithm that keeps the main feed diverse yet short no anxiety of unread count. Unfortunately it's iOS only and I have not seen open source RSS readers on android that take similar approach. Many support a "today" tab which does help in keeping the task of catching up more focused but if you follow high volume feeds that post a lot you end up having to scroll alot to see variety of content.

[0] https://apps.apple.com/us/app/feeeed-rss-reader-and-more/id1...