Let me rephrase. The only area in this changeset that added leisure=nature_reserve was https://www.openstreetmap.org/way/885956549

All of the rest was a splitting of a multipolygon, which was already tagged as leisure=nature_reserve. You can confirm it here: https://www.openstreetmap.org/relation/4220197/history

Are you only asking for Mount Chual Preserve to be reverted? I split off Rancho de Guadalupe and Cathedral Oaks because they are separate from the unnamed areas.