For me it helps connect the part of their resume that lists "technologies I've worked with" or "languages I know" part a bit more practically. I still take it with a grain of salt, but it does help when your dealing with a large volume of resumes.
For example if they list react as one of their skills and I see any react project, and I mean you could make a few changes to a generic create-react-app, I sort of know that at least this candidate does indeed know something about it and it gives us something to talk about in the interview.
Again, massive grain of salt, and if they don't have any projects it just alters the line of questioning a bit. Also larger projects they've worked on could very well be in private repos, but it doesn't take long to skim through a github profile.
Disclaimer that I'm biased towards this type of checking, because I had a built up github profile before I started applying for jobs.
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