The issue you're experiencing with Phase Sync after updating to v65 of your Oculus headset is likely due to changes implemented in the latest update. Meta's v65 update includes various enhancements and fixes, but specific details on Phase Sync adjustments are not explicitly listed in the release notes. This version introduces new features like improved passthrough environments, better support for physical keyboards and mice, and other performance tweaks.

However, community feedback and developer notes suggest that certain properties related to Phase Sync may behave differently in v65 compared to v63. The lag you're noticing when setting PhaseSyncStaticPadding to a positive value indicates that Phase Sync is still functioning, but the way it interacts with the system might have been modified, leading to the differences you're observing when using ADB commands like debug.oculus.phaseSync.

It's possible that Meta has altered how Phase Sync is managed or optimized in the background, which could explain why your previous methods of checking and enabling it are no longer yielding the same results. For detailed issues like this, checking forums and community discussions, or directly contacting Meta support, might provide specific insights or workarounds from other users experiencing similar problems.

For further information, you can refer to the Meta Quest v65 release notes and the related discussions in the Meta Community Forums.