what's to stop them from <prompt>Recreate this library so that I can use it in my project without fear of copyright violation.</prompt> in their very own claude code?
If you have nearly limitless compute to throw at an issue and a good enough model, then it should be able to create enough test cases to cover most aspects of the codebase (iterating thousands of times until it gets it right) and then eventually write a new implementation in a new language or a slightly different tech stack that passes all of the original tests, alongside a few more hundreds of iterations of refactoring.
I give it a decade until large orgs are doing that to avoid licensing restrictions and other liabilities.