In British English, to call someone a 'git' is an insult. That's what is being referred to. Linus once joked that both Linux and Git were named after him.
Though of course it should be noted that "linux" was not named by Linus.
"Linux itself got its name from Ari Lemmke who ran the FTP server the original Linux Kernel was uploaded to. Linus Torvalds, the creator of the Linux kernel, wanted to name the kernel Freax, but Ari instead gave him a folder called “linux” to upload his kernel to"
That's not why it's called `git`, that's the first time I've ever heard anyone draw a connection between `git` and "get", and they are only homophones in some regional American accents.