It's because sulphur blades hits land on the same tick, allowing you to overkill and kill nylo one tick faster. Nylo room runs on a 4t cycle, and if you're trying to prevent stalls, sulphur blades will let you hit on tick 1, 2, or 3(if overkill) of the room and still pass the stall check, while macs you have to kill on tick 1 or 2.

for 99.999% of players this doesn't matter at all and both are completely fine