TechCrunch reported that RSS is undead.
Another enormous challenge is discovery and curation. How exactly do you find good RSS feeds? Once you have found them, how do you group and prune them over time to maximize signal? Curation is one of the biggest on-boarding challenges of social networks like Twitter and Reddit, which has prevented both from reaching the stratospheric numbers of Facebook. The cold start problem with RSS is perhaps its greatest failing today, although could potentially be solved by better RSS reader software without protocol changes.
Rather than letting platforms or reader apps handle the curation and feed discovery, I believe the feeds would do better with manual curation. Bloggers are most likely heavy consumers of RSS feeds. Have them share their a feed list for a particular topic, kind of like how Twitter lists are.
Their readers would then be able to see where they get their inspiration, information, and influencers. The list is kind of an evolution of the blog roll. It could be a list of links or a downloadable OPML file to easily help beginners populate their reader apps.