yeah, that comment really seemed to show how out-of-touch the author really is. I haven't worked in a place that required a collared shirt in more than a decade. The last few interviews I've had, the interviewer wore a t-shirt and jeans.
He works in a consulting company in Texas. You need to project a certain level of professionalism to make your customers feel comfortable. Sometimes looking weird can be positive, e.g. for designers, but it can be a distraction.