RSS support in Mastodon is extremely rudimentary.
What I'm missing even more is a single Atom or RSS feed for the people I follow from my account.
On Reddit my account specific feed can be found at an URL that looks like this: https://old.reddit.com/.rss?feed=SECRET&user=USERNAME
On Pinboard it's at: https://feeds.pinboard.in/rss/secret:SECRET/u:USERNAME/
Adding a feed for every single person I follow to my feed reader (and manually keeping it in sync with what what my account actually follows) is not a solution that works.