It's true that majority of the users on Hashnode are web developers. When we started the community we seeded it with a lot of web content. This is partly because we are web developers ourselves - so it was easier for us to build nodes and discussions around these technologies. So, naturally Hashnode attracted primarily web developers as its early users.
I understand that topics like C++, OpenGL, CUDA etc are important. That's why we are working on new upgraded nodes which gives ownership to users. This time the focus is on launching new kinds of nodes systematically and building communities around them by having moderators, creators and influencers on the platform.
Once we launch the new upgraded nodes, we'll also have to tweak the feeds a little bit. We are working on it and are very excited about it.
So, expect to see some new and interesting nodes on Hashnode soon!