What about people that don't have much on their github? I like the idea of judging people based on their code, but I would say the majority of people don't feel like coding at home after doing it for 8+ hours day.
As far as I can see, there isn't really much of an alternative to coding in your free time. It's the only way to stay current unless your employer gives you time to improve your skills on the job. Which usually means you are using unproven tools in production.
Your choices are: only stay at jobs that let you greenfield the most cutting edge, experimental technology in production, constantly develop yourself by working on your own on the side, or expect to be outmatched the next time you look for a job (when those experimental technologies have had the kinks worked out and are now suitable for production. Then the cycle starts again).
Or you can do what my father's generation of programmers did: stay with the same company doing the same thing for so long that you are no longer in the game.
Currently working with a bunch of guys out of the game. Spending about 4 hours of free time a day for over a month was the only way to break into new tech and absolutely vital to my recent job search.
Learned some cool stuff, but also how terribly behind my company was
There's another issue - most of my code is stuff I've done for clients to make money (I can't show that on github), or stuff that I've done for myself to make money (I don't want to show that either).
That's happened in my field. I've helped a couple of C-suiters to recreate/edit their resumes. No one will advertise my services because they have to keep up the BS facade they've done everything by themselves. I wish the industry would call BS on excellent resumes, public speaking prep, EQ workshops, etc. We can't be good at all things but the smart exec knows how to find people with the right services and answers. Burns me up a bit.
I've been in the industry for a little while and none of my senior or experienced coworkers have impressive profiles or open source contributions. Unless you're junior, it's really not that big a deal compared to your actual experience and skills.
Your choices are: only stay at jobs that let you greenfield the most cutting edge, experimental technology in production, constantly develop yourself by working on your own on the side, or expect to be outmatched the next time you look for a job (when those experimental technologies have had the kinks worked out and are now suitable for production. Then the cycle starts again).
Or you can do what my father's generation of programmers did: stay with the same company doing the same thing for so long that you are no longer in the game.