As explained in another thread, nothing went wrong with the tooling and namespacing. The PyTorch devs misused a feature intended for a different use-case.
I took a look and the vulnerability that was exploited is warned about and described in the documentation.
> Warning > Using this option to search for packages which are not in the main repository (such as private packages) is unsafe, per a security vulnerability called dependency confusion: an attacker can claim the package on the public repository in a way that will ensure it gets chosen over the private package.