Self improvers are the ones reading Hacker News, going to conferences, and generally trying to hone their skill.
Dark matter developers are a class I've shamelessly stolen from https://www.hanselman.com/blog/dark-matter-developers-the-un... - which is definitely worth a read for the context, but the gist is that they're in this as a 9-to-5.
The trouble comes where the two groups meet. We can all learn about how to ask better questions and more generally improve our communication skills, but it's vastly more difficult to _make someone care_ to do so. We've all seen and empathized with https://www.nohello.com/, but if you link it to a dark matter coworker who behaves exactly this way, chances are they will see it as an attack, not as a recommendation - and that attack reflects poorly on you, rather than on them.