As the author of the article I can probably add some thought: none of those questions are difficult questions. A web developer who doesn't understand POST vs GET or http status codes is lacking the very foundations of web development. Many of the guys I've interviewed wanting exorbitant salaries can't answer these questions.
I.e they may have "been around" for a while but definitely aren't people I'd hire for senior roles. Apologies if you thought I considered these things as being hard. For context though, a senior dev can take these questions and expand them greatly.
Can you write/explain a POST request as an http request including header? What is your recall like if you had to write this request on a notepad? (ie you've not only seen an http 1.1 header and know what it looks but you've seen it enough that you can semi-remember it) How is a HEAD request different from POST/Get? In .Net land how is a PostBack different from a standard HTTP Post? What are your thoughts about this abstraction (love/hate?) and why? Etc etc.
They are what I call "feeder" questions. I have many of them, and they always start as beginner questions that evolve into discussion pieces. The best part about asking simple things, is you get real insight into the passion, loves/hates, fanatacism/religious thoughts on some topics and much more (ie. if someone starts talking about Nuget and mentions how it is like Ruby gems, this shows me that aren't just .Net devs and have a broader web programming view).
As a disclaimer though, these questions work for me but may not for you.
I also often do written problem solving/live coding tests, but I run mine a little differently from the norm. I like to give them a problem, ask them to talk through how they plan to solve it, and then get them to write (attempt to write?) pseudo-code (on paper with a pen) to solve it. This puts even the best programmers out of their element, and I feel gives me more insight into how they deal with a weird problem under strange conditions. I then ask how they would make their code testable, or how to refactor it. It is more of a discussion piece than anything, as this gives me insight into how they problem solve, what they know of any framework features that could help them, and much much more.
Smart guys are smart whether they know the latest IDE features or not. These are the people I want. I also will always have a brief I need to match though, so if I'm hiring for a web developer and your can't remember some HTTP status codes... well you aren't really a web developer (in my opinion). Again this is based on what I need so it might be different for you.