I do check.
But I don't rely on it.
It is just another conversation starter for me. It shows me what they might be tinkering with, where their non-work interests lie in the tech realm, what they might be studying.
I don't code review them or pick a part their pull requests to things. I don't use it to stalk them and see code quality.
Just one more thing to have in a conversational interview (so I can skip stupid things like whiteboard coding).
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.