Your aggressive tone is predictably inappropriate considering your failure at applying simple logic. You would only have a partial excuse if you're 11y/o or something.

There is f-droid the app store, and f-droid.org's main repo. See, it's not that hard.

just because they have an app that allows you to add other repos doesn’t mean those other repos are a part of f-droid

And that app is called... get it?

Because those other repos are not f-droid repos

Repos made to work in the f-droid app are not f-droid repos... wow

Is the f-droid.org's archive repo not an f-droid repo, too. lol.

Please tell me you're not an adult!

The thing is, you started on the right track:

Sync is not open source and Fdroid only allows open source.

Here, you are on the right. And you could have followed up later by simply pointing out that "Will it be released to F-Droid" usually means "Will it be on f-droid.org's FOSS-only main repo", but you decided to rant some weird incoherent shit, and insisted on dying on a hell of straws instead!