Interesting post. We're also building a business based on open-source / open-core software and have managed to build an active Github community around our first product (Klaro - https://github.com/kiprotect/klaro). It's a pretty simple tool that helps organizations to manage consent and protect their user's privacy on their website. We have other, more complex products in the making as well (e.g. https://github.com/kiprotect/kodex - a privacy engineering toolkit). What we found during the development of Klaro is that even a very simple product can require a tremendous amount of work to turn into a functioning product. I think we're almost there now but it took several months of building and refining.

For me, the main benefit of developing in the open is the great feedback and contributions we get from our community. A lot of people have reached out to us based on our open-source work, I don't think this would've happened if we had developed a closed-source tool.