Exactly this. The kernel seems like the least interesting part of an AR system. Also targeting x86, ARM and RISC-V for a new kernel is such a huge workload it makes no sense not to just re-use something already existing.

I had the same reaction! “legacy baggage” is a vague phrase. Without examples (like specific subsystems or bottlenecks), it’s hard to see how a custom kernel helps XR more than existing lightweight or RT kernels. If the team has benchmarks or case studies where Linux/Android gets in the way, that would make the argument much stronger.