The divine decision to punish the remaining people who fled to Egypt stands as an absolute and final decree. When God turns His attention directly toward the people, it is an act of intense, focused oversight. However, in this instance, His direct gaze is meant only to bring disaster upon them [מצודת דוד, ביאור שטיינזלץ].
The unique severity of this punishment becomes clear when compared to the earlier destruction of Jerusalem. The ruin of Jerusalem carried a hidden, future purpose for good. It functioned much like a seed that rots in the earth solely to sprout into a new crop. In sharp contrast, the fate awaiting those who went to Egypt holds no such promise. God directs His focus entirely toward their ruin, without any underlying plan for renewal or growth. The ultimate goal of this decree is the complete destruction of all the people of Judah who settled there [מלבי״ם].