I don't believe so much that Substack, or any other platform for that matter,  will "Adopt" Nostr as a protocol. However, it seems we are ripe for a Substack alternative that can utilize the Nostr Protocol in the back end.

I wonder what that would look like? The main feature of Substack, in spite of them trying to move users to the app, is that articles appear in users email inboxes. Perhaps some notification system letting Nostr users know new longform content is available? — This is a comment on: https://yakihonne.com/article/naddr1qqrrxdenxuenjqguwaehxw309ahx7um5wgknqvfw09skk6tgdahxuefwvdhk6qguwaehxw309ahx7um5wgknqv3w09skk6tgdahxuefwvdhk6qg7waehxw309ahx7um5wgknqv3wv3hhyctxv93hgmmj0yhx7un8qy28wumn8ghj7un9d3shjtnyv9kh2uewd9hsygpjgt70p7slgeqj5r4y2fgyen0ykech5w9y99rvtq4hwt7jq4qtmvpsgqqqw4rsjpgajz