Any windows power user or dev on a mac can follow a wiki, read a bit and learn.
Good for beginners? I didn't describe a beginner right here. Anybody with experience in computing will find arch straightforward and satisfying. Heck, a CS student would probably go through a first install process faster than I do after 5 years.
What are the concept involved? Partitioning, networking, booting... These are all familiar fields to tons of very normal computer users.
Arch can be a good first distro to anyone who knows what a computer is doing (or is willing to learn)
In short, like anyone else:
He's absolutely right, and utterly annoying