The subscription technology isn’t the issue here. The defining characteristic of email is that it’s open: anyone can add to your inbox if they have your address. With RSS, I have to explicitly allow new entries into my reader (a feed at a time). You can do that with email too: just add the sender to an allow list, and have that only work if the sender is verified (DMARC). Unfortunately, email client development stagnated and we don’t have good tooling for this.
RSS reader somewhat stagnated too, but seems to attract more indy love than email client development. Or more successful development, anyway.
(For what it’s worth, I do subscribe to his blog via RSS. My recommendation is NetNewsWire.)
