[2024] Probably a Bozo question but

No. But chunks can have a spawn mask that keeps the area relatively clear for awhile once you kill all the wilderness spawns in the area. It could have just coincided with you also clearing away the wrecks. Wandering hordes will still come through but wilderness spawns will end for a time. The time is different for the different biomes and also for city areas. I'm not sure on the exact times.