Maybe in some circles, yes. Many of us have had a career in industries where open-source contributions were basically out of question. I think Hejlsberg, Carmack, etc. are pretty respected and qualified despite not having 10k followers on GH.

I feel like this is sort of absurdly wrong. I don't think it's really possible to convey a lot of EE knowledge like accelerators, magnetics, and RF on Github (not easily anyways), but that's just as much if not more of a "tech qualification" than any software ability is. There's also a lot of software I've worked on that you can't open source, but is rather technical.

Really Github might be able to tell me if you can roll webapps, but for more sophisticated things, when I have been doing hiring in the past, it's really not been a great indicator. Some of the better developers I've met don't spend every waking hour programming (and don't want to), and don't contribute on the regular to Github projects.

Respectfully, that doesn't apply to regulated industries.