There's debate about that, because then you could apply that to any weapon. I'm assuming you're talking about realistically, if a lightsaber connects, it would kill right away, correct? Well then wouldn't that apply to a blaster shot from point blank range that hit someone in the face?
Accounting for "realism" is difficult in a video game where the whole point is to do damage and reduce your opponent's hit points as a realistic way to ensure that battles last longer than one shot and can actually be strategized for.