We have a partial port of GrapheneOS to the Pixel 11 series after a week of work on it. We're unable to complete the port due to lack of support for ARM hardware memory tagging in software, firmware and near certainly hardware. It appears Google cut an important security feature to save money.
Apparently the Linux kernel can emulate MTE in software:
https://lwn.net/Articles/833353/
The software MTE support in the kernel apparently predates the hardware support of the same, based on the above link.
Admittedly I might be misunderstanding something here, my confidence level is only 65%.