I don't know how I would define a platform. It can take up many different forms. In this case, it needs to provide creation tools and distribution tools. At that stage, it becomes a platform. You need to provide a pathway for these people to monetize on your platform. Well, they've sidestepped the ad stack completely.
This week Brian, Troy and Alex discuss Substack, why it's turning into a platform, and why e-mail may or may not be its future.
Some links: