Comment by noirscape

Killing Reader didn't just kill Reader. It killed the expectation of RSS to be a valid default consumption format of the internet. These days, if you use RSS, it's either relying on some legacy hidden feed feature that hasn't been shuttered yet (lots of Rails and WordPress sites that are like this) or you're explicitly adding RSS to your site as a statement.

Picking up the pieces after Reader was impossible because the entire RSS ecosystem imploded with it. Almost every single news site decided that with killing Reader, they wouldn't bother maintaining their RSS feeds, leaving them basically all "legacy" until they irrevocably break one day and then get shut down for not wanting to get maintained.