I am working on NDA Enterprise apps for 12+ years. I had no time for contribution and had very little activity on gh. On the other hand I've seen people who contribute a lot, but some of them were the most terrible people and developers I've had honor to work with that i even don't want to see them in my day to day life ever again.
Gh profile is only one tool among many others.
Hiring is too complicated topic to be only about having gh profile.
After all only yhing that matters is actually doing job and it only can be checked in doing real tasks within real team(or without, depending on situation).
Gh profile is good place for publishing your attempts with new tech you are playing with.
But oss contributions alone mean nothing alone, because how person behaves under work pressure/schedule/deadlines is what matters. Contribution on GH leaves everybody with context, rendering it unreliable source of.. anything.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.