Presentation matters, in dress as well as in attitude, comportment, and, of course, useful skills and ability.
"One of the saddest sights in the hotel conference hall is not so much the sloppily dressed interview candidate, as the ineptly dressed interview candidate — the one in the brand new, too-cheap, shiny, ill-fitting suit with too-short sleeves and too-long pants, rushing through the halls clutching a fake-leather briefcase. That person smells of desperation. Don’t let it be you."
I do a fair amount of interviewing and don't give a darn about how people are dressed as long as it shows some respect for themselves and for my time. Most people care about these things more than I do. However, one must sell oneself, not just to get a job but also to keep a job.