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.
Ironically, Microsoft platform as of yet still is pretty much a given that Linux may also run, with the exception of some of the Surface systems, but the ones no one wanted anyway. Apart from SecureBoot, Microsoft is picky enough about firmware specifications that are open, Linux can more easily be customized than random embedded things. Some things were rough, like ACPI implementations that didn’t comply strictly with the spec but microsoft happened to tolerate it, but fundamentally the Microsoft approach of outsourced everything makes for better chance for third party OSes.
Google became the new Microsoft
Ironically, Microsoft platform as of yet still is pretty much a given that Linux may also run, with the exception of some of the Surface systems, but the ones no one wanted anyway. Apart from SecureBoot, Microsoft is picky enough about firmware specifications that are open, Linux can more easily be customized than random embedded things. Some things were rough, like ACPI implementations that didn’t comply strictly with the spec but microsoft happened to tolerate it, but fundamentally the Microsoft approach of outsourced everything makes for better chance for third party OSes.