They might be a different demographic than people who know what a gwern is.
Maybe. On the other hand, would you entertain for even a second the thought of paying for an RSS feed? Personally, I can think of paying for an email newsletter if it's worth it, but the thought of paying for a blog with an RSS feed triggers an 'undefined' error in my head.
Also if I pay money for something, then it becomes a burdensome Rare and Valuable Possession I Must Now Find a Safe Place For, instead of a neat thing I can go look at, then forget all about, then go look up again after five years based on some vaguely remembered details.
Email is infinitely superior to RSS in this respect; everyone gets a durable copy and many people back up their emails (including you - right? right?). I have emails going back to 2004. In contrast, I'm not sure how I would get my RSS feeds from a year ago since Google Reader seems to expire stuff at random, never mind 2006 or whenever I started using RSS.
You're right about the paying part. I don't care to even begin worrying about how setting Google Reader to fetch something from beyond a paywall might work, but e-mail from a paid service makes perfect sense, tech-wise.
And now that you mention it, if I were living in an email client instead of Google Reader, I could probably get along just fine having stuff from my RSS subscriptions get pushed into my mailbox. Unfortunately, after 15 years I still use email so little that I basically consider it a hostile alien environment and haven't had enough interestin...
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