I imagine their notes are mostly dead. Or so if seemed last I looked before I deleted my account and my mailing list.

Substack will not integrate nostr unless they have total moderation control.

I follow a bunch of substacks on nostr. We updated rsslay to make markdown long form posts. You can see it running at rss.nos.social. Doesn’t work for their subscriber only content.

I found showing people yakihonne was a really powerful way of convincing people that nostr is good for long form content.