No "credentials" are being "harvested" here. It's all worthless data, save for the statistics.

Do most installations create a git user account with login permissions?

There's no such thing as an account with or without login permissions. Normally you need a git account. And that means you can log in to it. And then you have to try and configure your ssh server so that after logging into the git account, you can only run the git server (I forget the command). If a mistake is made with this configuration then you can log in or port forward or X forward or file transfer as git.

This is a terrible idea because it's blacklist-based security. Places like GitHub have their own ssh server that only runs the git server and nothing else.

I suppose /usr/sbin/nologin is not a thing?

https://www.man7.org/linux/man-pages/man8/nologin.8.html

That's a hack. It's a login shell that, once you have already logged in and run the shell, prints a message saying you can't log in or run a shell, and then exits.

It does not stop you from, say, logging in to SSH and then starting a port forward. Or running a command in a way that bypasses the login shell. ssh will always pass it to your login shell but other ways can be vulnerable.

SSH bastions would like a word I guess. You can authenticate, but you definitely can’t login (which is also the case for git over SSH).

Having a root password of "toor" is very clever. Nobody will figure that one out.

toor was a default password for many devices for decades.

I've used unix-like OS's for 28 years and I don't remember coming across it as a password.

It is a common username (see: https://en.wikipedia.org/wiki/Toor_(Unix) ), the machine I am typing this on has it.

It was the default password for the root user in Kali Linux for a while.

Back when it was called Backtrack if my memory serves right. I remember being puzzled that it was not the case anymore one day and they even switched to regular user around when Kali became a thing

Slackware used it in the late 90s IIRC.

Did you check out the statistics on the site? They listed 1233456, 12345, 1234,123 and 1 on the toplist of password.

If we are going to be clever we should follow the statistics and go for 12 that where not on the toplist!!

Or even better, 21. Reverse it to add another layer of obfuscation.

You are right.

12 - Rank 318

21 - Rank 523

I'm surprised that '12' is so low on the list.