uhm no not really? I mean reproducible builds are used to cross verfiy that it is the same binary in this case, but like android has no mechanism to do that, this is not how it works.
that a build should be reproducible is more about your second point and doesnt really have anything to do with fdroid, as far as i know
Edit: these links should explain it all: https://discuss.grapheneos.org/d/21675-fdroid-security/2
capitalism was kind of never democratic i think, considering so much is basically dictated by the people who “own” it, which feels more like a dictatorship/ feudalism