Personally, I'd rather have employers judge me on code I've written for projects in my GitHub profile, code that I've meticulously architected and refined over periods of weeks, months and years, targeted to solve non-trivial, relevant real-world problems in an elegant and expressive manner, over some code that I'm forced to spit out on the spot under unrealistic time constraints solving nerdy CS algorithm puzzles and doing low-level performance optimizations that's never realistically worthwhile to implement from scratch in production (at least for the kinds of problem domains I'm interested in).
I do understand the possible misrepresentation resulting from judging candidates based SOLELY on GitHub profiles, but for those with presentable contributions/projects readily available on GitHub, I feel it makes for a much fairer representation of the candidate than the alternative.
Me too, and that's why I set up our hiring process such that candidates are welcomed to supply code samples via github and other means if they can. However we recognize that this simply isn't feasible for everyone, and it's not held against anyone if that's how it is.
For me personally, nearly all of the work I've done over the last handful of years is on github, however most of that is contained in private repos that I can't share. I don't think that's what people mean when they say that I'm supposed to have everything on github :)
I do understand the possible misrepresentation resulting from judging candidates based SOLELY on GitHub profiles, but for those with presentable contributions/projects readily available on GitHub, I feel it makes for a much fairer representation of the candidate than the alternative.