Open source depends on people wanting to work on it. Firefox is a very intimidating beast under the hood. Making it interesting is a vital important goal.
I get that, and that's exactly what the Hacks blog is for (it has always done this masterfully). The recent posts on Hacks and Mozilla Tech on Medium have done this really well I think.
I don't think the tone here necessarily does anything for generating interest though. This is highly subjective, but at least for me it made for a jarring read and I lost interest pretty quickly. As I said above, I respect the intent behind the article, but I just found it very odd.
Different strokes I guess. There's plenty of documentation out there on CSS engines that you'd find readable while others lose interest pretty quickly. The diversity in approaches ensures that the pool drawn into Firefox development is diverse.
