@udon @charliebrownau @coin @furgar @ryo
Okay, so, everyone reading this should try this just to see how fucking retarded this is. Actually, you're right locale-gen is there, it's not Debian or Devuan at all, it's because of a universal, absolutely fucktarded problem with it, that also makes it not work with doas.

For some ungodly reason locale-gen only works with sudo, just like visudo (you need to be root AND still use sudo to even fucking set up sudo, which is also retarded). You can look at the pictures, I was root, after using su, and even being root, it doesn't work without sudo. Why did I use su? Because I couldn't get doas to work in the Debian VM, and the Devuan VM is so fresh I didn't bother setting up sudo. I use doas in all of my systems, but in the Debian VM, with the exact same configuration, it just doesn't work and I have no idea why, so I tend to just run su in one terminal and use that, and then I don't have to keep typing the password or set up persistence in sudo.

Now, I just got doas working in the Devuan VM (maybe they had the same issue as Debian before, but it's fixed, keep in mind that the Debian VM is a little behind, I think). It works. But guess fucking what? You can't use locale-gen with doas either! IT HAS TO BE SUDO. Even as fucking root! Who designed this abomination?!

You can tell that I don't install new systems very often these days. I have been using doas for a couple years and only noticed that right now.

Anyway, to use locale-gen, you HAVE to install sudo. Except in the system I'm using to type this, I don't have sudo, and it works. It could be because sudo is a symbolic link to doas? Actually, I just tested it, and the answer is no. It doesn't work on Devuan even that way! So, this doesn't work on Debian-based distributions for some reason.

WHY?!