After weeks of Microsoft bouncing every mail our server sent to any of their mail properties (due to, I guess, some history on the IP before we owned it), I have begun to doubt the premise that no one owns email. The major providers can make your mail server useless to 20%, or more, of email recipients. That's a pretty big club to wield. (I understand why a mail provider would block, and I've instituted IP-based blocks on my own mail servers in the past. It's just that email is such a mess, and there's not a good way to solve it.)
But, I would love it if RSS made a huge comeback. Twitter, facebook, Instagram, etc., I'd love it if I didn't have to open any of them, but could still follow my friends posts. There's no technical reason for them to be walled gardens, only business reasons, which are at odds with my privacy and general happiness.