It's important to note here that the term "package" is overloaded here. For lack of better disambiguation: a distribution package is what you create by having a setup.py and/or pyproject.toml file, using a build backend such as Setuptools to create a "wheel" and/or "sdist", and optionally publish them to PyPI. An import package is what you create simply by having a folder in a place that Python will search for modules, such that you import the folder name in the source code and get a "package", which is actually just a module. It doesn't need an __init__.py file (that serves a more subtle purpose) and it is represented by the same type as a module created from a .py file (not even a subtype).

Anyway, I think this question is not quite organized right to be most useful for canonicals. I guess I'll have to prioritize the Q&As I had in mind on that topic....

BTW, I think I have an old post on the site Meta where I laid out some possible future import Q&As. Seems like a good time for both of us to revisit that.

I would argue that the ambiguity of the term "package" is a problem with Python rather than with this question. I could not imagine someone asking this kind of question to actually know about the ambiguity of "package".

Now that I've read the self-answer, the intended scope of the question is clearer to me. I might propose an edit later.