Hi Rebecca.

The reason why I have faith in Medium's longevity and tend to think Substack's star will wane is mainly because of the different subscription models.

Here on Medium, one single subscription gives access to and helps support ALL writers. The individual subscription model that Substack, Patreon and other places use is unsustainable in the longterm. Writers here are being tempted to try Substack out and may get people to sign up to their email list but will soon discover that persuading those same people to _pay_ for a subscription is a very different matter.