Earlier quoted context omitted.
I suspect if you look in your passwd file you’ll find lots of users. Does nginx really need to read the files in your home directory?
Very few computers running nginx have human user accounts with more than dotfiles in the home directory. Meanwhile desktops run everything on the same account because defining usable security policies between users is basically impossible.
Sure, in production. I don’t think that’s generally true though. It’s pretty common for developers to run an http server for test purposes. But anyway, that was just an example. I could have said cups.