لَيْسَ كُلُّ طَالِبٍ قَدْ سَجَّلَ الْمَشْهَدَ.
Not every student recorded the scene.
كُلُّ طَالِبٍ لَمْ يُسَجِّلِ الْمَشْهَدَ.
Every student failed to record the scene.
The first rejects the claim that all students recorded it; it is compatible with some doing so. The second predicates non-recording of each student individually. The strength and scope of the statements differ.
The interaction of fronting, quantifiers, and negation is semantic, not merely stylistic. The presence of kull does not by itself license identical universal readings of the two constructions.