Open sourcing something like this feels like marketing more than anything else. They suffer from the same "cold start" problem that social apps do. For the project to thrive, there needs to be an existing fanbase to improve and support it. Is what makes Wordpress great the fact that it's open source? No. It's the community of builders that surround it. Would anyone realistically be willing to spin this stack up in th…
And still, people do get that done, and it is great that you have the self hosting option if you don't like their pricing (or if they ever go suddenly bankrupt, compromising your business).