"[RSS is] an easy way for readers to quickly discover released and updated articles." This is true. And there's nothing in that statement about how frequently a site updates.
Telling sites to reduce the number of entries in a feed and telling users to decrease the refresh frequency is a bad idea for sites that update frequently. Very few self-hosted rss readers allow for per feed refresh rates (freshrss is the only one I've found that does I think) so to capture everything on sites that update frequently but have tiny feed sizes I have to run separate cronjobs. That's after asking them to increase the feed size.
