Python packaging can be a bit overwhelming at first. The main reason for that is the confusion about proper tools for creating Python packages. Anyway, once you create your first package, you will see that this is not as hard as it looks. Also, knowing proper, state-of-the art packaging tools helps a lot.
You should know how to create packages even if you are not interested in distributing your code as open source. Knowing how to make your own packages will give you more insight in the packaging ecosystem and will help you to work with third-party code that is available on PyPI that you are probably already using.
Also, having your closed source project or its components available as source distribution packages can help you to deploy your code in different environments. The advantages of leveraging the Python packaging ecosystem in the code deployment process...