Disclaimer : I tried to read as much as I could of both arguments, but to be honest I didn’t review everything completely before writing this. However, I dare however writing this, hoping it could bring another point of view in this debate.
As a developer, I daily work on “fully open-source software” and open-core ones (
hence my presence on this forum 
).
I do agree on the main issue raised by @wolftune about the difference we should make between free and open-source softwares, often supported and developped by a core-team that gathers members from different companies (examples that are coming to my mind : Ruby on Rails, Linux, Kubernetes, etc.), and open-source and partially open-core softwares like Baserow. These software often rely on a single company that is actively maintaining it (examples : Metabase, Airbyte, Gitlab).
I think Baserow has nothing to fear to say how they work, in fact, the CTO Oliver Maes talked about it recently on this same forum : Founder Chat: What was the process for defining the Baserow business model?
In practice, I suggest that using the terms Community Edition and Enterprise Edition would clarify things for everybody : many people are fine using what’s available, for a company paying a few bucks is ridiculous compared to the value the software could bring.
In a wonderful future I hope to see, it would be delightful to see other companies coming around not only to use Baserow, but to develop around it, hence allowing the Baserow company to focus on community features more than enterprise ones. It would be a win-win for everybody. As a community member, I’m actually betting on such possible future.