Depends what you seek from a sunglass. Most people seek both, protection and style. If you're seeking only protection then the article you posted makes sense if you're into style then it's something else.
Personally, I'm into both, my last sunglasses I bought cost me around 65euro. I like it and I don't regret buying it though it's not cheap.
Exactly like me , I bought a Ray Ban sunglasses 3 months ago but I lost them recently :frown: .
Then, I just went for the cheap ones in the gas stations and black markets .
And two weeks ago ,I bought Carrera sunglasses , I really like their designs .
I bought one similar to this one :
Mine is silver not brown , costs me around $200 .