Why it's cool... I don't know. I agree it helped me in the early days of my career, but at this point, as a senior developer I can pick up new technology much faster than my early days. I can come up with a working solutions much faster.

I like my job, and I like programming... But there are other things I like too.

So, why do I need to work long hours and program outside of my job? I have good enough communication skills to convey my experience. If I'm not hired for not having an active github account, or a side project, there are five other companies that would.