One needs to pay attention to the term "open source" in their repo. These days, there are efforts to shield OSS products from those who would simply drop them into AWS and take away part of one's financial model. That happened to Mongo, ElasticSearch, Neo4J, and who knows what else. So, there are all manner of new kinds of licenses which are not OSS approved. While it's true that this product's source code is
open for viewing -- it's there in the repo -- one particular folder: /premium contains code which is not OSS and subject to a license which is the equivalent of an "annual maintenance fee - per seat" which many AGPL vendors sell to those who want to work around the AGPL license. I see it as a novel (compared to others) approach, but, when you consider what code they put into /premium, you have to ask: what good is the platform to me without those components?
I think we will continue to see creative ways to block misbehaving capitalists who take advantage of the OSS comunity.