Loving Krishna means loving everyone because Krsna is in their heart. Conversely, applying that logic backwards, if you don’t love everyone, it means that you are not loving Krsna. Using the root and leaves example, if the leaves are looking healthy, it is to be understood that the root is receiving nourishment.
In SB, eleventh canto, it is explained that only the kanishta or neophyte sees Krsna in the temple, but not in the hearts of all, and fails to respect and develop loving relationships w