RSS's decline was/is due to 2 main factors. The first is a contagion effect. People just started to assume RSS was 'over' because big names like Twitter and Cr

RSS's decline was/is due to 2 main factors. The first is a contagion effect. People just started to assume RSS was 'over' because big names like Twitter and Craigslist dropped support after they realized supporting it isn't in their interest. The second much more powerful factor is that the vast majority of users just want to see new stuff when they scroll. They probably never bothered to use RSS (you'd find these people on cat meme sites most of the time), and if they did they were happy to give it up the first time they saw the Facebook news feed. The fact that far greater numbers of people were watching the Fb news feed meant that RSS was more or less instantly irrelevant just based on sheer numbers of eyeballs available.