These are entirely different systems to me. We just happen to use bookmarks to keep track of feeds / updating websites. I have lots of bookmarks I keep for static content that I want to refer to constantly. Blog posts, specific documentation pages, Stack Overflow answers, etc. It's nice to just begin typing "Python async..." chrome's suggestions will show me my bookmarked link. I've been looking into a better way to do this as my bookmarks grow, searching by page content would be a nice feature too. (I hear about Pinboard a lot on HN, and I've been meaning to look into it. This manager seems neat as well. However that's for another comment/thread).
But that way of using bookmarks is a different goal than "bookmarking" a news website, a forum, etc. And I agree with you in that regard, that bookmarks still seem the best way to manage this is sort of silly. What you describe is something else, and certainly something which would be useful, but it's not a bookmark. A bookmark doesn't tell you when your favorite author has released a new book, or turn the page in a book for you. It holds a specific page that you'd like to return to, and it does that job very well.