here is a list of 100+ not official fdroid repositories. https://github.com/userkilled/FDroid-List-Repository
F-That
I'd definitely consider this as being "available on F-Droid".
> It looks like F-Droid does not have any apps matching your search string "grayjay"
You're using a third-party repo that allows proprietary apps. The real F-Droid only allows FOSS ones.
The F-droid team does not have a high bar to be dicks. They do it to ensure their users get binaries that match the published code to prevent increasingly supply chain attacks.
The standards are there for good reason, and if you do not understand those reasons, then use a license that allows the people that do understand to distribute your software for you.
Very very few software engineers understand supply chain attacks or how to prevent them.
Who decides what is cool? That's right, the marketing departments of huge corporations...