> it looks like the software Google is shipping intentionally doesn't use MTE on the Pixel 11 hardware. That raises the question of...what does Google know is wrong with MTE on the Pixel 11?

Apple replaced MTE with an upgraded version that can run in synchronous mode all the time without the performance hit.

> Consider that MTE can be configured to report memory corruption either synchronously or asynchronously. In the latter mode, memory corruption doesn’t immediately raise an exception, leaving a race window open for attackers... We believe memory safety protections need to be strictly synchronous, on by default, and working continuously.

https://security.apple.com/blog/memory-integrity-enforcement...

Google may just be getting ready to follow suit.