This is a place where I think there's a huge element of privilege involved. If someone is coming from a background where they are single, have money in the family, only have to support themselves... almost certainly they can/should have some side projects that they've done.
However, not everyone has that level of luck and blessing in their life. Maybe they have to care for an ailing parent, are the first in their family to go through college. Maybe they're spending every extra hour they have dealing with immigration challenges.
I once worked with a junior developer who was a refugee, supported his mother (who didn't speak any English) and sister, while also having to deal with a sibling who would literally steal from them and was in trouble with the law. I didn't learn about all of this until long after I started working with him; these aren't exactly the types of things that would come up in an interview.
You never know the road someone else is having to walk. If that road doesn't enable them to be doing side projects, we shouldn't hold that against them... and neither do I think we should force them to wear their difficulties in public to "justify" their lack of side projects. We should judge them based on their skills and ability to do the job.
You are bringing an excellent point. There are many personal/social/economical circumstances by which a person won't be able to have personal projects.
I came to the comments specifically to say something similar. While I generally recommend students do things outside their core coursework to differentiate themselves, it's a double-edged sword because there's a level of privilege that is required (and the more you have of it, the more time you have to spend on side projects...)
Making it a requirement (whether explicitly or not) is almost up there with unpaid internships - students from lower socioeconomic backgrounds can't always take opportunities and the advantage gap widens for reasons that have nothing to do with skill or passion.
Requiring side projects of experienced devs is just unrealistic. Once you've had demanding jobs for a few years you may no longer have time, let alone energy, for meaningful side projects. Add into that that age dictates we're more likely to be parents or caring for aging parents, and suddenly I'm reminded of why there's still a low number of women in technical roles - but aside from that it starts sounding like we expect both men and women to have no life outside of work even when they have 10 years' professional experience.
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