> Although that might be true for you it's very much false for 99% of Android's user base.
But 99% of the Android's user base doesn't want to sideload (and they shouldn't).
> Android is a nightmare to compile for
I don't know when was the last time you tried compiling for Android, but in the last decade it has been a matter of running `./gradlew build`. If this doesn't work, then the project you are trying to build is badly structured.
> For all intents and purposes, we should accept that Android users must be able to install pre-compiled open source software.
And they are: 99% of Android users install apps from the Play Store, and it works just fine.
> In sane operating environments there's the option of reproducible builds, which guarantee that a particular binary comes from a particular source, if Google cared about Android users, they would make that available for Android too.
It's simply harder than you make it sound, and it only works for open source software (how do you reproduce a build for which you don't have access to the sources?).
> nobody would care about side-loading being unavailable
Sideloading is not becoming unavailable! It will just require being a verified developer if you want to sideload on a Google-certified Android phone. If you actually care, there are enough possibilities to install an alternative OS (though I would recommend GrapheneOS). And if for some reason it's not an option but you still care, you can build the app from source and install it on your Google Android.
> In other words, installing other OSes is a high-value goal and it makes sense to use every occasion to put pressure on Google to move in that direction - and there is no better occasion than pushing for open sideloading.
My point is that this makes no sense! Pushing for unverified sideloading makes strictly nothing for alternative OSes. Let me repeat that: it strictly doesn't help. Alternative OSes are not affected by this new Google policy. They are affected by other issues, but nobody talks about them.
> It should be abundantly clear that if you can't get open sideloading you will never get open OS install.
I think you do not understand how alternative OSes work, because this is plain wrong.
And don't get me wrong: I think we are on the same side. I don't like monopolies. I just feel like fighting against the verified sideloading on Google Android is just completely missing the point.