MTE is an optional feature for ARMv8.5 and is only available via ARMv9 in practice. Snapdragon doesn't provide it but they told us they're likely going to add it by 2025/2026.
Pixel 8 and Pixel 8 Pro are the main option with it. MediaTek and Exynos have theoretically added support for it but that doesn't mean any device with their latest flagship SoC theoretically supporting it actually has it available and working.
We want to support other devices and consider this the main blocker because Exynos is not widely used outside Samsung and Snapdragon is better at overall security than MediaTek. Qualcomm dropped the ball on MTE but they're quite good at security overall. It doesn't matter outside our perspective because MTE is not being used in production by others yet, which is why Qualcomm didn't prioritize it.
