the Tl;DR is that Owncloud has a non-open source Enterprise version with extra features you need to pay for
This isn’t any different than a lot of other softwares, though… Nextcloud has the same Enterprise pricing/features shit, too. https://nextcloud.com/enterprises/
Actually, so does Photoprism. https://www.photoprism.app/features
It’s not self hosted, but I spent some time curating the news feed on Bing. It works well enough that I felt comfortable switching from Google Feed, and I don’t have to worry about self-hosting random news feeds.