The distinction is that you cannot substitute the word "figuratively" in these examples, because it does not mean "figuratively". If I say "I figuratively am g

The distinction is that you cannot substitute the word "figuratively" in these examples, because it does not mean "figuratively". If I say "I figuratively am going to kill him", you're highlighting the figurativeness of the act. You're stressing that you're not actually going to kill him. The meaning of the sentence is "I'm going to kill him... but not really". If I say "I'm going to kill him" or "I'm literally going to kill him", which mean basically the same thing, it's still implied to be metaphor. But what's being stressed here is the closeness to the metaphor becoming actually literal. The meaning of the sentence is "I'm SO angry with him that I'm ALMOST at the point of killing him". It's subtle, but there's definitely a distinction. "Figuratively" is a dehyperbolization (it's not really gonna happen), "literally" is a hyperbolization (it is hyperbolically really close to happening).