Yes, it's basically trying cargo cult "coolness" , of course that isn't a 100% bad thing if it helps encourage people to get out and try something new.
If you take up a hobby just to appear cool then there's every chance you won't stick with it very long.
I'm sure there are many people who have taken up certain hobbies just to impress people and then found them legitimately enjoyable and fulfilling and they would continue to do them even if they became the most uncool thing.
Also since nerds have a tendency to hyper-focus on things in depth they will likely bring their nerd skills to something non nerdy and outdo the non nerds at it.
If you take up a hobby just to appear cool then there's every chance you won't stick with it very long.
I'm sure there are many people who have taken up certain hobbies just to impress people and then found them legitimately enjoyable and fulfilling and they would continue to do them even if they became the most uncool thing.
Also since nerds have a tendency to hyper-focus on things in depth they will likely bring their nerd skills to something non nerdy and outdo the non nerds at it.