Earlier quoted context omitted.
You'd be surprised how fast a society can collapse if it's left to wannabe Einsteins and Feynmans and Elon Musks and nobody is there to dig ditches, clean the garbage and work the assembly line. Or how better a society would be without tons of well paid white collar jobs (advertisers for one).
But how am I supposed to know what to buy!
1) Detailed specs by the manufacturer (that have to be valid or get large fines -- e.g. regarding speaker frequency response, or drug side effects, or cosmetics effectiveness, etc.).
2) Reviews by the media
3) Reviews by laymen
4) Word of mouth