Both these questions are related in the sense it reflects how large the audience needs to be to a viable business. Question is how much VC money has been burnt

Both these questions are related in the sense it reflects how large the audience needs to be to a viable business. Question is how much VC money has been burnt on it - perhaps it’s bootstrapped well and it can succeed at a much smaller scale; it’s definitely possible. However in the long run, it’s somewhat of an easily replicable stack / feature set, particularly as I assume that most highly successful writers would want to control their branding and prefer not to be on substack if they could reach the same audience. Which they likely can’t. Substack’a SEO abilities will be key to its success as that is in many ways it’s main feature (everything else can be replicated by any one of the millions of web developers out there). In that sense, becoming the landing page of bookworms would be a significant achievement and to answer your question an important goal for any considerable success. I base this on the fact that it seems like they have spent a fair bit in building the platform and it’s not as bootstrapped / low in capital as it may need to be to be viable as a smaller entity. But I’m guessing very much here! Is it really that different to hosting blogs, personal websites or to Medium.com? They just have the mailing list feature, but for most that doesn’t work because it takes a long time to build your own mailing list, so the target audience of writers is small. My 2c