Interestingly, a lot of open-source companies have built defensible businesses -- a list is over at http://oss.cash. Recent IPOs include Mulesoft, Elastic, Mongo, Fastly...
More specifically to Gatsby, we don't actually see ourselves in the hosting business, more in the "collaboration" business -- most websites have teams of nontechnical folks that are reviewing sites before they go live, creating and editing content, and so on. We're building Gatsby-specific collaboration tooling, starting with CMS Preview.
A good comparison here would be Github -- nobody thinks of Github as "Git hosting", they think of Github as the place where developers collaborate together on projects.
More specifically to Gatsby, we don't actually see ourselves in the hosting business, more in the "collaboration" business -- most websites have teams of nontechnical folks that are reviewing sites before they go live, creating and editing content, and so on. We're building Gatsby-specific collaboration tooling, starting with CMS Preview.
A good comparison here would be Github -- nobody thinks of Github as "Git hosting", they think of Github as the place where developers collaborate together on projects.