Not using Github doesn't stop others from posting your code on Github with incorrect licenses. It becomes a massive game of whack-a-repo
Takes practice, but it's a skill that can be mastered like any other.
The code in question is not something that anyone needs to own. Rather, it's what anyone would write, faced with the same problem. It's stupid to make humans do a robot's job in the name of preserving meaningless "IP rights".