It's antithetical to their business strategy. They charge for premium accounts to give access to private repos. Nothing wrong with that, but OP should probably try out Gitlab if he wants an enterprise-level solution for free.
I'm not OP, I'm GP. Second, I fully understand git, github, gitlab, etc.
I'm specifically discussing a situation wherein someone has uploaded non-licensed code to github. I am not advocating for this. I am discussing what should be the default behavior for a repo if unlicensed. Another alternative is not having the repo be usable at all (so not private) if one attempts to bring it public without a license.
Get over yourself. I was referring to OP of this particular sub-thread, meaning you.
And you are continuing to misunderstand how this works. If you can view it, you can copy it. Nothing prevents someone from viewing a public repo. So nothing prevents someone from copying it. Therefore any attempt to make it difficult is just a PITA.
That's why Github has a default license for all non-licensed public repos. Because it's a public repo. If it wasn't supposed to be available to copy, the source code shouldn't have been made a public repository.
So again. If what you're looking for is a private repo solution, Gitlab offers this enterprise-level solution for free. You are barking up the wrong tree.