In my experience, the opposite of the aforementioned 50-something hoodie wearer would be someone with a Oxford shirt and jacket, ie well-dressed, but not hip. And they might dress up similarly in their free time, when they're not with their co-workers. So the "Han Shot First" tee might be as much an unwanted disguise as the "business casual" dress code the startup bros avoid.

I'm not saying that one shouldn't adapt a bit, but dyed hair and "How do you do, fellow kids" clothes overshoot the goal by a good bit.