The problem is, that alot of humanity still relies on cliches to communicate "base-truth". Suite and tie looks professional in movies, so you get more credit and respect for superficial looks on the job.

One must not support such a ridiculous look based culture by heart, its instead more a - "I want to reap the benefits & rewards from idiots in awed reference to work uniforms"

Ironically the same happened to the hoodie, after various hackermovies. Wear a hoodie and sit with a laptop, obviously improves your coding ability.