I feel like this is increasingly indicating KSR station does not fit (my) existing mental models, and the station might belong to a new category of station that contains only itself: rural stations.

KSR station is built in an area with a lack of any high-density development / any new town development. Quite rural. Other theoretical "rural" stations simply don't exist (e.g. Kwu Tung, Hung Shui Kiu, etc.) or no longer exist (e.g. Tai Po Kau). We might simply have no precedents for this.

In basically every other railway station in HK, the railway station itself doesn't suddenly cause nearby roads to promote towards primary/secondary; the nearby roads *are* already primary/secondary by themselves, regardless of whether the station exists, let alone whether park-and-ride exists.