Yes, it's absolutely true. Supporting writers one at a time is unsustainable. I think it works great for people who have something valuable to add to a high profile conversation. A friend of mine began her Substack in around October and built it to 500 subscribers, including 30 paying, by Christmas. Because her voice is adding something of value to an existing conversation.

For creative writers, probably not so much. But I also think there is likely value in building an audience over there if you have other things to promote, and I'd already decided that I want to self-publish a book of memoir essays from my childhood, hopefully this year. Obviously, I'd leverage my Medium audience but perhaps also an audience of both free and paying subscribers on Substack too.