[acatton]

I would create an unwarranted bias towards people working for companies doing mostly opensource. If their previous job was writing safe code for rockets and airplanes, the candidate will very likely be qualified to write embedded code for tractor/cars but incapable of showing previous work due to confidentiality agreements.

[voidUpdate]

I mean, I was hired out of university, and I had a portfolio of programming and a github ready to go to show that I could program, without having a previous job to show code from at all, let along one with an NDA

[squeaky-clean]

Do you have an updated portfolio though? For many people working in private industry, they aren't allowed to share code from their job, and their previous portfolio projects are from college, which would not be good enough for a mid or senior level role. Would you hire a (non-junior) frontend developer who shows you a React todo list they made 8 years ago?

[acatton]

You were young without kids or any other responsibilities, so you had spare time to nerd around. Not everybody is in that position. With this requirement you would create a bias towards single parents or folks talking care of the handicapped partner/parent, as well as another bunch of other categories of people.