As described in open source issue https://github.com/stackrox/stackrox/issues/18836

Users would like a way to more easily manage system policies when policies-as-code is enabled, in a way that does not involve a manual export of all existing system policies via the UI.

This was discussed internally when developing the initial feature as a way to avoid drift with a GitOps-first approach, but I do not believe a solution was ever prioritized.