I shlepped around for about 9 months after graduating college until I got my first job that made use of my degree. It was at Manufacturers Hanover Bank in New York City. I was so excited. I remember my Boss in my first week saying to me "remember Fred, always dress for and. be prepared for the next job you want, not the one you are in now". I still get what he was saying. When you are in a larger organization, you have lots of loose relationships. And there is lots of attrition. If you look the part, you may more likely be considered to fill an opportunity that emerges. I think some of this is dated, some is specific to Wall Street, but some of it is relevant today. I like this groups msg. Dressing for success is something one has to consider in different places.
And bias goes both ways. Try wearing a suit and tie everyday to a tech company in San Francisco and see how much they consider you for a new product manger role. The 'next position' concept works. But what you dress like varies by company, and by role you want.
Be aware. And when in doubt.. ask the Jobcase community. Someone here knows the right answer for the situation you are in.