> Your very rigid view of the world is so distorted to the point of being absurd. You know damn well that the vast, vast majority of spying on Android is done in userspace.
Most local privilege escalation (LPE) attacks used to escape the app sandbox, browser renderer sandbox or other sandboxes are done with kernel exploits. There are plenty of LPE vulnerabilities in AOSP userspace code but plenty in the userspace driver and HAL code too. It's definitely the kernel ones which are used most in practice. There are an endless stream of serious Linux kernel vulnerabilities and regularly patching the kernel is crucial to privacy/security.
Nearly all data extraction attacks are currently done with Linux kernel USB exploits and will likely need to switch to Linux kernel radio and other driver exploits when the USB attack vector is unavailable. If you care about privacy then you probably care about protecting your data from someone who obtains your device. That heavily depends on both hardware-based security features and security updates for the firmware, kernel, drivers and HALs in addition to the AOSP portion of userspace.
Disk encryption doesn't truly work on most Android devices for the majority of users because they're missing Weaver throttling support in hardware so a random 6 digit PIN can be easily brute forced once an attacker gets control over the OS. Most users don't use a strong passphrase so Weaver is critical for them. A software rate limiting implementation doesn't hold up to serious attacks.
> A good OS that allows you to remove permissions from apps and further isolate things does a lot for privacy.
Privacy depends on patching privacy vulnerabilities and shipping the standard current generation privacy protections. Android 17 without our improvements has a decent permission model and app sandbox. That's not the case if there are a bunch of privacy holes in the kernel, missing privacy features due to an outdated kernel and privacy holes in the drivers/firmware too such as tracking via Wi-Fi identifiers other than the randomized MAC.
Privacy also heavily depends on security. That's why GrapheneOS puts so much work into security rather than only privacy features. Having a nice privacy model doesn't do any good if adversaries can exploit the OS remotely, from a malicious/compromised app or another way. It doesn't provide any protection for users against many widespread attacks. Play Store regularly catches and bans a lot of apps which use LPE vulnerabilities to take over people's devices. Far more happens via distribution methods without app store review or scanning systems.
We heavily improve privacy with features like Contact Scopes, Storage Scopes, Sensors toggle, Network toggle and other changes. These improvements aren't anywhere close to the highest priority on a device missing crucial privacy and security patches. It's better for someone to have a stock Android device with decent updates than a partial port of GrapheneOS with many of the privacy and security features miss
> I respect your desire to refuse supporting anything but pixels, but please don't pretend that alternate OS on old devices don't improve privacy and security.
Using those devices with LineageOS has nowhere close to reasonable privacy or security. You're missing years of Linux kernel patches, not only patches for the drivers, firmware and HALs. Not patching Linux for years is definitely important and it's not hard to exploit it if it's not getting basic updates, especially without having a lot of kernel hardening. Linux kernel exploit protections are far weaker than Android userspace exploit protections. It's the softer target and has far more privileges so that's what gets targeted. It has massive attack surface for apps despite the massive attack surface reduction done by Android. Android's standard exploit protections including attack surface reduction for the kernel are drastically better in the latest stable releases. It's not only the privacy/security patches which are important but also the standard privacy and security improvements.
The purpose of GrapheneOS is not making a highly insecure device somewhat less insecure while also making it less secure in other ways by losing verified boot and other security features.
GrapheneOS certainly doesn't refuse to support anything other than Pixels. We have an official OEM partnership with Motorola Mobility. We're working with Motorola on multiple devices meeting our requirements and providing official GrapheneOS support which should be available in under a year. You're claiming we aren't doing one of the major things we're actively working on and have announced with Motorola. We're also open to working with other OEMs once we have more resources available. It's not an exclusive partnership, but we're very busy and don't want to spread ourselves too thin.
So far, no other OEM has been both willing and able to make devices meeting our requirements so far. Samsung could do it but currently doesn't allow another OS to make use of many important security features right now since. Samsung permanently cripple devices if they're unlocked and locking it again with the stock OS doesn't restore all the functionality including security features, but even more security features are missing for an alternate OS than what's permanently disabled. They also make it extremely difficult to properly support their devices. They're welcome to change all of this and we could support their devices in the future.