I don't think your problem is that it's not open-source. Your problem is marketing and positioning.

For one thing, the copy on the website is not commercially oriented at all. I sense your earnestness, but copy needs to be clear and compelling. A reader needs to come out of it thinking - YES! this is just what I needed. You start off by mentioning a combination of two tools I've never heard of, and why would I even care, I'm reading about YOUR thing. Look up Pedro Cortés on LinkedIn - he does a lot of video reviews of SaaS landing pages.

Two - and just as important - the use case is so abstract, you're counting on your users to imagine how they would use it. Instead, for a knowledge organizing tool, it should be pitched at the challenges people regularly have trying to organize knowledge. (For example, having a gazillion links and tabs. I could imagine this as something really helpful to solve that problem, especially if you can then export it all in some convenient structure [CSV, JSON].) You've got the core of a product, but it's not quite a product yet, that's my impression at least. It could be though! Best of luck