Turns out systemd independently does this, although not in every case. If you have unset locale, it changes it to C.UTF-8 for X (gdm3) but not for console logins.
It'd be good to have this consistent both for X vs console, and systemd vs other inits/rc systems. Meow! -- ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢠⠒⠀⣿⡁ Remember, the S in "IoT" stands for Security, while P stands ⢿⡄⠘⠷⠚⠋⠀ for Privacy. ⠈⠳⣄⠀⠀⠀⠀