That's more on F-Droid, no? If someone said "Download from Cydia", I would not expect it to download it from Saurik's official repository called "Cydia/Telesphoreo". Using the same name for the app (store kit) and the repository is just a bad design choice, especially if the reference implementation comes with only the said repository.
What about software you download from a third party yum or apt repo? You would still say you're getting it from yum/apt, albeit not from a red hat or canonical hosted yum/apt repo. Same for f-droid. They're just called f-droid repos and the biggest repo that currently exists is also run by f-droid.
The wording was not intentionally construed to imply anything of the sort. It's been updated now to say "with" instead of "from"
For sounds like the right word not from.
it's the same as linking to your .exe or .img and saying "get it from microsoft/apple". no it's not. you are just using those platforms ability to handle links and extension of functionality.
it is in no way the validation from those platforms that wording like they do imply