It sounds simple on the surface. You copy a link on a site into a feed reader app. Then whenever that site updates you get a nice readable article on the app.
But that sounds like something that could be accomplished locally. Why does every RSS reader I run into require an account or otherwise rely on the cloud?
They do not need an account ever.
There are a few companies that run reader apps that do require an account.
RSS was very common until Google created Google Reader, everyone centralized on it for some reason, then they killed it. Then Google and Apple and Firefox removed rss feeds from their browsers.
There are independent apps not is hard to find good ones
I used to use RSS to get a Craigslist search feed so new listings I searched for would just pop up next to my email in Thunderbird. it was nice