Part of "professionalism" is the recognition that you can be whoever you want to be on your own time, but while you're at work your personal identity is partially subsumed into your identity as a member of a profession. That means you dress, decorate, talk and behave in a way that's a bit more neutral and respectable than you might in your college dorm room.
This is a bit dull, sure, but it also enables all sorts of people to work together effectively by papering over their individual differences with a shared professional identity. The fact that your coworkers are of a different sex or generation to you and like different things is pretty immaterial when you're all wearing suits, sitting at undecorated desks and talking about work. Nobody will be alienated by your dick jokes, because nobody makes dick jokes.
Greater professionalism is the solution to many of the tech industry's problems.
