I'm vaguely aware of Lace Code but I've honestly never seen it used or even really mentioned outside of the internet. Part of me is curious if it was ever a really a thing outside of maybe a few scenes scattered about. Feels like something that, because the concept is kinda intriguing, the internet may have overblown. But I wasn't around in the 80s, so I'm not sure. Curious to hear from anyone who was actually part of the scene back then.
I wouldn't say it's still extremely common, but some people do use it. One of my friends used to wear both purple AND yellow laces, I remember the questions were endless and it went over everyone's head. I think colored laces in general get mistaken as a intrinsically nazi thing pretty often unfortunately.