I would not be drawing connections to reality from government actions. California imposed COVID curfew [1] just because they could, not because the viruses are nocturnal. At best, if there was actually any thought put into it at all, it's to trap feral cats at night, when they are most active, and if any house cat gets trapped too the owner can be told to get stuffed and ticketed for violating the curfew.

1. https://www.kcra.com/article/california-limited-curfew-covid...