The official statement, is from Google and ARM, not from me.
From my links above, the TL;DR; snippets are
> Google is committed to supporting MTE throughout the Android software stack. We are working with select Arm System On Chip (SoC) partners to test MTE support and look forward to wider deployment of MTE in the Android software and hardware ecosystem.
> Starting in Android R, for 64-bit processes, all heap allocations have an implementation defined tag set in the top byte of the pointer on devices with kernel support for ARM Top-byte Ignore (TBI). Any application that modifies this tag is terminated when the tag is checked during deallocation. This is necessary for future hardware with ARM Memory Tagging Extension (MTE) support.
And from https://android-developers.googleblog.com/2020/02/Android-11...
> We’re also enabling heap pointer tagging for apps targeting Android 11 or higher, to help apps catch memory issues in production. These hardening improvements may surface more repeatable/reproducible app crashes in your code, so please test your apps.
For the chips without MTE they plan to configure the kernel to randomly target processes for fuzzing.
https://android-developers.googleblog.com/2020/04/android-11...
https://developer.android.com/ndk/guides/gwp-asan
> GWP-ASan heap analysis - Android 11 uses a variety of tools to harden security-critical components in the platform and apps. In DP3, we’re adding GWP-ASan as another way to help developers find and fix memory safety issues. GWP-ASan is a sampling allocation tool that detects heap memory errors with minimal overhead or impact on performance. We’ve enabled GWP-ASan to run by default in platform binaries and system apps, and now you can now enable it for your apps as well. If your app uses native code or libraries, we recommend enabling GWP-ASan and testing as soon as possible.
> GWP-ASan is enabled on some randomly-selected system applications and platform executables upon process start-up (or when the zygote forks)
And from ARM official communication, https://community.arm.com/developer/ip-products/processors/b...
> Only recently, Google announced that it is adopting Arm’s MTE in Android. This is exciting news, with Google showing its continued commitment to security in the Android ecosystem. It also shows the strength of our MTE offering, with the article stating that the technology makes “it very hard (if not impossible) to exploit memory bugs.” Alongside the security benefits, the disruption caused by not addressing memory safety bugs reduces user satisfaction and increases the cost of software development. With all these threats to the Android Ecosystem, you can understand why Google has made the commitment to MTE!
So those are the words from Google's Android team and ARM, whatever ARM CPU are being shipped, or alternative CPUs that Android devices might still adopt or be using.