system
A chat on subreddit /r/me_irl
human
It is hard to teach kids whose mother tongues doesn't feature z-sound, so any attempt at "zee" would be indistinguishable from "jee"(G), which would cause unnecessary trouble. Way easier to teach "zed" (no problem if it becomes "jed").
gpt
Interesting. In my language, 'z' doesnt exist, but we substitute it with 's', not 'j'.