Does hp fall to 0 if a creature is knocked unconscious from failing a save, and if not, how does the unconscious condition end?

I was looking at the Prismatic Beetle Swarm, and it says that "In bright light, a creature within 30 feet that looks at the prismatic beetle swarm must make a successful DC 13 Wisdom saving throw or be blinded until the end of its next turn. If the saving throw fails by 5 or more, the target is also knocked unconscious."

If a creature in range falls unconscious from the dazzling light of the swarm, do their hitpoints automatically drop to 0? It doesn’t say so specifically, like it does for drowning rules and other things, nor does it say so in the actual unconscious condition. And spells like Catnap and Sleep don’t make hp drop to 0, although I feel like unconsciousness from falling asleep is different from falling unconscious in this manner.

If their hp does not drop to 0, how does the unconscious condition end? Does the unconscious creature still need healing?