I think this didn’t get picked up enough in Nostr, but nostr:npub108pv4cg5ag52nq082kd5leu9ffrn2gdg6g4xdwatn73y36uzplmq9uyev6 is launching building a substack like competitor on nostr, called letr.co.

nostr:note1chupd3hj99ahdd6rvnlgh670q589sv4aaecjm3ta3v25h0d3h6asq44qf0