The problem with that article, and the argument it presents, is that it assumes far too much at the outset, upon which the rest is based.
Unfortunately, its premise is flawed and, thus, everything that follows the exposition is flawed.
For the tl;dr crowd, to summarize: People who like balance over fun gameplay are idiots. It's ok to have classes 1-shot everyone and everything while others suck so bad even the Devs are at a loss to explain their function. So long as the game is fun for everyone, right?
The response being, of course, no. A game designed with balance in mind, and maintained as much as possible (with necessary adjustments made) throughout its life, can be as much (or more) fun than being over-powered compared to the content.
There are some good points, but I disagree with the solution.
Giving more to make players more powerful and then adding new areas with new powerful monster is the vicious circle that made Ultima Online a senseless fight of semi-gods vs apocalypse demons, the whole with awful colours. The first universe where people kill dragons in five hits. That makes you dream.
Plus, the more you add, the less you can balance.