There’s a difference between source available and open source. For example, actually being allowed to distribute modified versions is pretty damn important:
Restrictions
No Distribution of Modified Versions: You may not distribute modified versions of the software, whether in source or binary form.
No Forking: You may not create, maintain, or distribute a forked version of the software.
Official Distribution: Only the maintainers of the official repository are allowed to distribute the software and its modifications.
Not actually open source but ok.
What is “actually open source”, if “here’s the source code” is not?
There’s a difference between source available and open source. For example, actually being allowed to distribute modified versions is pretty damn important: