Ask HN: Should You Work for Free as a Freelancer?

The idea of this question came after seeing this YouTube video: https://www.youtube.com/watch?v=Bqi62NGdCZw&t where the OP says that it could be beneficial for new freelancers to work for free to get a portfolio piece. I believe that working for free is unnecessary, but I'd like to get HN's opinion on the matter.