I'd argue that: a) as an industry we have far less of a clothes == professionalism association (and that's definitely a good thing) b) if anything dressing in a suit is an indication that you've primarily worked for older, more formal companies where the technology and management practises are behind the times and you're therefor less likely to be a skilled professional and/or need help to adapt to the culture of cutting edge technology companies.

Also the implication that we're 'not on their level' due to not wearing a suit is absurd.