It doesn't come off as snobby or even pretentious, merely facile. The author has publications in distributed systems in reputed journals, is currently researching and teaching on distributed systems, and has worked with the Scala community for quite some time so at the very least she is competent and knows the subject.
Dismissing content because it's written in markdown without providing good reasons, such as quality of content or specifically how the presentation hinders proper communication is indeed quite lazy. If you want people to take you seriously, please try to be more precise in your criticism.
What does writing in Markdown have to do with the complexity of the topic? Heather Miller is an assistant professor at CMU and well respected and certainly an expert in this context. Clearly she believed Markdown was sufficient for her purpose and/or wanted to leverage the other benefits beyond just its simplicity. Did you see that book is being rendered on a site? http://dist-prog-book.com/chapter/2/futures.html
Reacting to a bad comment with an even worse comment is not ok here. It's against the site guidelines, and you've been doing it a lot. We've had to ban you before for that, so would you please stop?
If you're posting to HN, you're responsible for helping to take care of this place, to the best of your ability and awareness. If others are wrong, correct them respectfully. If they are ignorant, teach them. If you know more, share some of what you know so the rest of us can learn. Tearing others down helps no one, and worsens the very things you're complaining about.
I'm sure you wouldn't litter in a city park just because others do, nor would you fail to put out a campfire just because you were mad at other campers. Please bring those values here.
