Monetization is an issue due to the general lack of ads and tracking, but there are some possible solutions, like Ars Technica’s model of $50/yr for access to the full-text RSS feed.
I had no idea they did that, and that's a really genius idea. I'd happily pay that for sites I like reading so I can pull the content in and read it how I want to rather than deal with the absolute dumpster-fire of a mess that the modern web is.
$25. $50 is the pro++ version. i say this as a happy subscriber. I know a few other sites that do the same, and being able to access a plaintext feed is a huge plus to me.
Only the first image of Arstechnica's image is available in a feed, though, and videos they sometimes embed in the header do not show. I assume both are bugs, but I can open the page if the article is interesting.
If your question is specific to the Ars Technica subscription, there is no authentication. Each subscriber is given a unique feed link (for whatever they want to subscribe to) so any fetch operation for the link is tied to the subscriber. Ars says that it monitors the use of feeds and will take action if any abuse is detected, but doesn’t go too deep into explaining that part.
Some other services like Stratechery follow the same model, AFAIK.
I guess for RSS you could pull a New York Times and have the RSS feed just link to the website, ads / paywalls included once the user clicks on the link.
Monetization is an issue due to the general lack of ads and tracking, but there are some possible solutions, like Ars Technica’s model of $50/yr for access to the full-text RSS feed.