In ye olden times, there wasn't Medium. Sites where everybody could write whatever they wanted. And so sites like Medium could run their own feed of sorts, and send me a digest email with what they think I want to read.
The King(s) of Google do have a strong blogging community in Blogger, but it was never supposed to be, nor never will be, a backstop against Facebook. It would be better for Google to work within Facebook on this, as bloggers in WordPRess, or MEdium, or whatever announce on social media, guess whose ads are running on the blogs? And I myself as a dev, I'm still searching for the best articles for development practices and more. They don't see that need for us to subscribe to RSS. It's the King(s) of Facebook, Twitter, etc., that need to listen. Giving us a way to watch our subscribed RSS feeds in their own ecosystem will give them the edge on content aggregation.