I was doing Android development recently and apparently the official SDK builds needed to build the app aren't FOSS, and actually FOSS versions are difficult to get. I still can't wait until Linux phones are a thing, Android is such a shitshow nowadays and even GrapheneOS is still at the mercy of Google's ecosystem. (also still no aarch64-linux support for the build tools either)

because many People who loves privacy

almost 12 of us ... i jest but seriously, everyone using Apple and >90% of Android users don't care. Google knows this and they just bang on about this being best for Android users to ameliorate any concerns around governance issues.

Even many supposed staunch, so called privacy advocates, will complain they can't change because banking or some such, so they stick with the status quo as every minor inconvenience is seen as an insurmountable wall.

So i expect some bloviating initially and then acceptance. In 5 years, no shits given (headphone jack, expandable storage saw the same sort of thing)

tl;dr press x for doubt (x)

Motorola will release a phone with GrapheneOS in 2027, it would be a good pick.

Don't forget about the new automatic Google play services check that app developers can enable with a single click on build. That automatically blocks the app from working on any degoogled ROM

So, did I understood correctly that just getting pixel with GrapheneOS is way out?

Is there an alternative to Android and iOS in the US? I'm trying to degoogle but what other phones are there?

I think you're overestimating the de-Google community.
I'd be astonished if there was 10 million of us. Compared to a few Billion normies, we're a rounding error in their accounting.

Can you advertise f-droid in an app on play store? Or offer free features on a link that teaches how to f-droid yourself?