Ask HN: What sites should I have in my RSS feed?

I recently switched to RSS and I'm really enjoying how distraction-free reading is. (For anyone looking to do the same, I highly recommend NextCloud News if you have a server for cross-platform syncing). However, my RSS feeds are a little thin. Turns out finding RSS feeds is difficult, and finding ones that work well with the entire article and not just a header is next to impossible. What are some good websites with in-depth thoughtful articles that I can get via RSS? I honestly don't care about the content, just looking for material I can read and feel like I've learned, or expanded my own thoughts, distraction free.