1. You have to get users to clickthrough to get your ad revenue, but you also need enough content in the RSS to encourage them to click at all. It feels like you put effort into this thing that prevents users from spot checking your website, which reduces your revenue. And you're hosting the RSS feed, too, so it costs bandwidth!
2. Twitter is easier to use (for you and your audience), is where the audience is, and is "good enough".
Twitter is absolutely what eventually killed my RSS usage. Human curated links in my Twitter feed, vs the firehose of articles that often fill up the RSS feeds of many sites.
I've used countless 'read it later' services like Pocket, Instapaper etc over the years (even some on PalmOS...), but for me at least the combination of Twitter plus the much more reliable cellular data we have now has made them less appealing.
Twitter has advantages beyond just the links being shared - the tweets themselves are often interesting to me, and the list of people I follow has been carefully built over time to the point it would be annoying for me to switch again now.
I'm sure these are great options for others though, but I don't think I'm alone in using Twitter as a kind of curated RSS replacement.
Maybe 7 years ago I built a service that would track links from your Twitter feed, mainly because I was posting links I found interesting and wanted a way to refer back to them later.
I intended to have it track all links from people you follow too, to give a curated list of links, but Twitter was aggressively making changes to restrict their API so this became impossible.
1. You have to get users to clickthrough to get your ad revenue, but you also need enough content in the RSS to encourage them to click at all. It feels like you put effort into this thing that prevents users from spot checking your website, which reduces your revenue. And you're hosting the RSS feed, too, so it costs bandwidth!
2. Twitter is easier to use (for you and your audience), is where the audience is, and is "good enough".